138 Logical question on input and output

Here are a few examples of logical reasoning questions based on input and output patterns:

Example 1: Number Pattern

Question:
What comes next in the sequence?
2, 5, 10, 17, __?

Solution:
The pattern is increasing by consecutive odd numbers:
(5 – 2) = 3
(10 – 5) = 5
(17 – 10) = 7
The next odd number would be 9.
So, 17 + 9 = 26.
Answer: 26.

Example 2: Letter Series

Question:
What comes next in the series?
A, D, G, J, __?

Solution:
The series follows a pattern of increasing the letter by 3 places in the alphabet each time.

• A → D (3 steps)
• D → G (3 steps)
• G → J (3 steps)
  So, the next letter will be 3 places after J, which is M.
  Answer: M.

Example 3: Number Series

Question:
Find the missing number:
4, 9, 16, 25, __?

Solution:
These numbers are squares of integers:
4 = 2²
9 = 3²
16 = 4²
25 = 5²
The next number should be 6², which is 36.
Answer: 36.

Example 4: Input and Output Relationship

Question:
If the input is:
1, 4, 9, 16, 25
What is the corresponding output?
2, 3, 4, 5, 6

Solution:
The output corresponds to the square roots of the input numbers:

• √1 = 1
• √4 = 2
• √9 = 3
• √16 = 4
• √25 = 5
  So, the output would be the square roots of the input numbers.
  Answer: The output is 2, 3, 4, 5, 6.

Example 5: Logical Pattern

Question:
Input:
4, 8, 12, 16
What will be the output if the rule is to multiply by 2?

Solution:

• 4 × 2 = 8
• 8 × 2 = 16
• 12 × 2 = 24
• 16 × 2 = 32
  Answer: The output will be 8, 16, 24, 32.

Example 6: Number Series with Alternating Operations

Question:
What comes next in the sequence?
1, 4, 2, 5, 3, 6, __?

Solution:
The pattern alternates between adding 3 and subtracting 2:

• 1 + 3 = 4
• 4 – 2 = 2
• 2 + 3 = 5
• 5 – 2 = 3
• 3 + 3 = 6
  The next step should be:
• 6 – 2 = 4.
  Answer: 4.

Example 7: Square Pattern

Question:
What is the missing number?
1, 4, 9, __, 25

Solution:
The numbers are perfect squares:
1 = 1²
4 = 2²
9 = 3²
The missing number is 4², which is 16.
Answer: 16.

Example 8: Letter Sequence

Question:
What comes next in the series?
A, C, E, G, __?

Solution:
The pattern follows every second letter in the alphabet:
A → C → E → G → I.
Answer: I.

Example 9: Alternating Number Series

Question:
What comes next in the series?
1, 10, 2, 9, 3, 8, __?

Solution:
The sequence alternates between adding 9 and subtracting 1:

• 1 + 9 = 10
• 10 – 8 = 2
• 2 + 7 = 9
• 9 – 6 = 3
• 3 + 5 = 8
  The next step should be:
• 8 – 4 = 4.
  Answer: 4.

Example 10: Cube Pattern

Question:
What comes next in the sequence?
1, 8, 27, 64, __?

Solution:
These are cubes of integers:
1 = 1³
8 = 2³
27 = 3³
64 = 4³
The next number will be 5³, which is 125.
Answer: 125.

Example 11: Even/Odd Number Pattern

Question:
What comes next in the series?
2, 6, 12, 20, __?

Solution:
The pattern increases by consecutive even numbers:
(6 – 2) = 4
(12 – 6) = 6
(20 – 12) = 8
The next difference should be 10.
So, 20 + 10 = 30.
Answer: 30.

Example 12: Divisibility Pattern

Question:
What is the missing number?
12, 24, __, 48, 60

Solution:
The pattern is multiplying by 2:

• 12 × 2 = 24
• 24 × 2 = 48
• 48 × 2 = 96
  Thus, the missing number is 96.
  Answer: 96.

Example 13: Input and Output with Reverse Order

Question:
Input:
1, 2, 3, 4
Output:
4, 3, 2, 1

Solution:
The output is simply the reverse order of the input numbers.
Answer: 4, 3, 2, 1.

Example 14: Adding and Subtracting in Sequences

Question:
Input:
1, 3, 6, 10
What is the corresponding output?
2, 6, 12, 20

Solution:
The pattern is adding consecutive numbers:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 + 4 = 10
  For the output, we are multiplying the input by the number added to it:
• 1 × 2 = 2
• 3 × 2 = 6
• 6 × 2 = 12
• 10 × 2 = 20
  Answer: 2, 6, 12, 20.

Example 15: Pattern with Multiplication and Addition

Question:
What comes next in the sequence?
2, 6, 12, 20, 30, __?

Solution:
The difference between consecutive numbers increases by 2 each time:
(6 – 2) = 4
(12 – 6) = 6
(20 – 12) = 8
(30 – 20) = 10
The next difference will be 12:
30 + 12 = 42.
Answer: 42.

Example 16: Arithmetic Progression (Addition)

Question:
What is the next number in the series?
3, 7, 11, 15, __?

Solution:
This is an arithmetic progression with a common difference of 4:

• 7 – 3 = 4
• 11 – 7 = 4
• 15 – 11 = 4
  So, the next number is:
  15 + 4 = 19.
  Answer: 19.

Example 17: Decreasing Pattern

Question:
What is the missing number?
81, 64, 49, __, 25

Solution:
These are perfect squares in decreasing order:
81 = 9²
64 = 8²
49 = 7²
The missing number will be 6², which is 36.
Answer: 36.

Example 18: Number and Position Pattern

Question:
What comes next in the sequence?
1, 2, 4, 8, __?

Solution:
Each number is double the previous number:

• 1 × 2 = 2
• 2 × 2 = 4
• 4 × 2 = 8
  The next number is:
  8 × 2 = 16.
  Answer: 16.

Example 19: Prime Number Pattern

Question:
What comes next in the sequence?
2, 3, 5, 7, 11, __?

Solution:
The sequence follows prime numbers:
2, 3, 5, 7, 11 are prime numbers.
The next prime number is 13.
Answer: 13.

Example 20: Exponential Growth

Question:
What is the next number in the series?
2, 4, 8, 16, 32, __?

Solution:
The pattern involves multiplying each number by 2:

• 2 × 2 = 4
• 4 × 2 = 8
• 8 × 2 = 16
• 16 × 2 = 32
  So, the next number is:
  32 × 2 = 64.
  Answer: 64.

Example 21: Adding Squares Pattern

Question:
What is the missing number?
1, 5, 14, 30, __?

Solution:
The differences between the consecutive numbers are consecutive square numbers:

• 5 – 1 = 4 (2²)
• 14 – 5 = 9 (3²)
• 30 – 14 = 16 (4²)
  The next difference should be 25 (5²).
  So, 30 + 25 = 55.
  Answer: 55.

Example 22: Increases by Multiplication

Question:
What is the next number in the sequence?
2, 6, 18, 54, __?

Solution:
Each number is multiplied by 3:

• 2 × 3 = 6
• 6 × 3 = 18
• 18 × 3 = 54
  So, the next number is:
  54 × 3 = 162.
  Answer: 162.

Example 23: Fibonacci Sequence

Question:
What is the next number in the series?
0, 1, 1, 2, 3, 5, __?

Solution:
This is the Fibonacci sequence, where each number is the sum of the two preceding ones:

• 0 + 1 = 1
• 1 + 1 = 2
• 1 + 2 = 3
• 2 + 3 = 5
  The next number will be:
  3 + 5 = 8.
  Answer: 8.

Example 24: Multiplication Pattern

Question:
What is the next number in the sequence?
1, 2, 6, 24, __?

Solution:
This is a factorial pattern:

• 1 × 1 = 1
• 1 × 2 = 2
• 2 × 3 = 6
• 6 × 4 = 24
  So, the next number is:
  24 × 5 = 120.
  Answer: 120.

Example 25: Repeated Operations

Question:
What comes next in the series?
5, 10, 15, 30, 35, __?

Solution:
The pattern alternates between adding 5 and multiplying by 2:

• 5 + 5 = 10
• 10 + 5 = 15
• 15 × 2 = 30
• 30 + 5 = 35
  The next step is:
  35 × 2 = 70.
  Answer: 70.

Example 26: Series with Squares and Cubes

Question:
What is the missing number?
1, 8, 27, 64, __?

Solution:
The sequence consists of cubes of integers:

• 1 = 1³
• 8 = 2³
• 27 = 3³
• 64 = 4³
  So, the next number will be 5³, which is 125.
  Answer: 125.

Example 27: Adding Increasing Numbers

Question:
What comes next in the sequence?
1, 3, 6, 10, 15, __?

Solution:
The pattern involves adding consecutive numbers:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 + 4 = 10
• 10 + 5 = 15
  The next step is:
  15 + 6 = 21.
  Answer: 21.

Example 28: Arithmetic and Geometric Pattern Combined

Question:
What is the next number in the sequence?
2, 4, 12, 48, __?

Solution:
This sequence involves multiplying by 2, then multiplying by 3:

• 2 × 2 = 4
• 4 × 3 = 12
• 12 × 4 = 48
  So, the next number will be:
  48 × 5 = 240.
  Answer: 240.

Example 29: Alternating Addition and Subtraction

Question:
What comes next in the series?
3, 8, 6, 11, 9, __?

Solution:
The pattern alternates between adding 5 and subtracting 2:

• 3 + 5 = 8
• 8 – 2 = 6
• 6 + 5 = 11
• 11 – 2 = 9
  So, the next number is:
  9 + 5 = 14.
  Answer: 14.

Example 30: Square and Add Pattern

Question:
What is the missing number?
1, 5, 14, 30, __?

Solution:
The differences between consecutive numbers are increasing by consecutive integers:

• 5 – 1 = 4
• 14 – 5 = 9
• 30 – 14 = 16
  The next difference should be 25 (the next perfect square).
  So, 30 + 25 = 55.
  Answer: 55.

Example 31: Reverse Order of Operations

Question:
Input:
5, 10, 15, 20
Output:
20, 15, 10, 5

Solution:
The output is simply the reverse order of the input numbers.
Answer: 20, 15, 10, 5.

Example 32: Multiplying Alternately

Question:
What is the next number in the series?
3, 6, 12, 24, __?

Solution:
Each number is multiplied alternately by 2 and 3:

• 3 × 2 = 6
• 6 × 2 = 12
• 12 × 2 = 24
  So, the next number will be:
  24 × 3 = 72.
  Answer: 72.

Example 33: Doubling Pattern

Question:
What comes next in the sequence?
2, 4, 8, 16, 32, __?

Solution:
Each number is multiplied by 2 to get the next one:

• 2 × 2 = 4
• 4 × 2 = 8
• 8 × 2 = 16
• 16 × 2 = 32
  The next number will be:
  32 × 2 = 64.
  Answer: 64.

Example 34: Adding Fibonacci Numbers

Question:
What is the next number in the series?
1, 1, 2, 3, 5, __?

Solution:
This is a Fibonacci sequence, where each number is the sum of the two preceding numbers:

• 1 + 1 = 2
• 1 + 2 = 3
• 2 + 3 = 5
  The next number will be:
  3 + 5 = 8.
  Answer: 8.

Example 35: Increasing Powers of 2

Question:
What is the missing number?
1, 2, 4, 8, __?

Solution:
This sequence involves doubling each number:

• 1 × 2 = 2
• 2 × 2 = 4
• 4 × 2 = 8
  So, the next number will be:
  8 × 2 = 16.
  Answer: 16.

Example 36: Alternating Multiplication and Addition

Question:
What is the next number in the series?
1, 3, 6, 18, 21, __?

Solution:
The pattern alternates between adding 2 and multiplying by 3:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 × 3 = 18
• 18 + 3 = 21
  So, the next step should be:
  21 × 3 = 63.
  Answer: 63.

Example 37: Addition of Consecutive Odd Numbers

Question:
What comes next in the sequence?
1, 4, 9, 16, __?

Solution:
The sequence consists of the squares of consecutive integers:
1 = 1²
4 = 2²
9 = 3²
16 = 4²
So, the next number is 5², which is 25.
Answer: 25.

Example 38: Subtracting Increasing Numbers

Question:
What is the missing number in the series?
50, 45, 39, 32, __?

Solution:
The pattern involves subtracting consecutive integers:

• 50 – 5 = 45
• 45 – 6 = 39
• 39 – 7 = 32
  The next step should be:
  32 – 8 = 24.
  Answer: 24.

Example 39: Dividing by 2 Pattern

Question:
What comes next in the series?
16, 8, 4, 2, __?

Solution:
Each number is divided by 2 to get the next one:

• 16 ÷ 2 = 8
• 8 ÷ 2 = 4
• 4 ÷ 2 = 2
  So, the next number will be:
  2 ÷ 2 = 1.
  Answer: 1.

Example 40: Increasing Pattern of Prime Numbers

Question:
What comes next in the series?
2, 3, 5, 7, 11, __?

Solution:
The pattern follows prime numbers:
2, 3, 5, 7, 11, and the next prime number is 13.
Answer: 13.

Example 41: Repeating Addition Pattern

Question:
What comes next in the series?
1, 3, 6, 10, 15, __?

Solution:
Each number is the sum of the integers starting from 1:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 + 4 = 10
• 10 + 5 = 15
  The next number is:
  15 + 6 = 21.
  Answer: 21.

Example 42: Multiplying by Increasing Numbers

Question:
What is the next number in the series?
2, 6, 24, 120, __?

Solution:
Each number is the product of the previous number and an increasing integer:

• 2 × 3 = 6
• 6 × 4 = 24
• 24 × 5 = 120
  So, the next number will be:
  120 × 6 = 720.
  Answer: 720.

Example 43: Reversing the Digits

Question:
Input:
123, 456, 789
Output:
321, 654, 987

Solution:
The output is simply the reverse of the digits of the input numbers.
Answer: 321, 654, 987.

Example 44: Alternating Between Operations

Question:
What is the next number in the series?
1, 2, 4, 3, 9, 4, __?

Solution:
The pattern alternates between multiplying by 2 and adding 1:

• 1 × 2 = 2
• 2 + 2 = 4
• 4 – 1 = 3
• 3 × 3 = 9
  So, the next operation will be:
  9 – 1 = 8.
  Answer: 8.

Example 45: Subtracting from a Constant

Question:
What is the missing number in the series?
20, 17, 14, 11, __?

Solution:
The pattern subtracts 3 from each number:

• 20 – 3 = 17
• 17 – 3 = 14
• 14 – 3 = 11
  The next step will be:
  11 – 3 = 8.
  Answer: 8.

Example 46: Multiplication by Powers of 3

Question:
What comes next in the sequence?
3, 9, 27, 81, __?

Solution:
Each number is multiplied by 3:

• 3 × 3 = 9
• 9 × 3 = 27
• 27 × 3 = 81
  So, the next number will be:
  81 × 3 = 243.
  Answer: 243.

Example 47: Adding Consecutive Numbers

Question:
What is the next number in the series?
1, 2, 4, 7, 11, __?

Solution:
The pattern adds consecutive numbers:

• 1 + 1 = 2
• 2 + 2 = 4
• 4 + 3 = 7
• 7 + 4 = 11
  So, the next step is:
  11 + 5 = 16.
  Answer: 16.

Example 48: Adding and Subtracting in Alternation

Question:
What comes next in the sequence?
5, 10, 8, 13, 11, __?

Solution:
The pattern alternates between adding 5 and subtracting 2:

• 5 + 5 = 10
• 10 – 2 = 8
• 8 + 5 = 13
• 13 – 2 = 11
  The next operation will be:
  11 + 5 = 16.
  Answer: 16.

Example 49: Increasing by Squares

Question:
What is the next number in the series?
1, 4, 9, 16, __?

Solution:
The numbers are perfect squares:
1 = 1²
4 = 2²
9 = 3²
16 = 4²
So, the next number will be 5², which is 25.
Answer: 25.

Example 50: Factorial Pattern

Question:
What comes next in the series?
1, 2, 6, 24, __?

Solution:
This sequence follows the factorial pattern:
1 = 1!
2 = 2!
6 = 3!
24 = 4!
So, the next number will be 5!, which is 120.
Answer: 120.

Example 51: Adding Odd Numbers

Question:
What is the missing number?
1, 4, 9, 16, __?

Solution:
The differences between consecutive numbers are increasing odd numbers:

• 4 – 1 = 3 (odd)
• 9 – 4 = 5 (odd)
• 16 – 9 = 7 (odd)
  So, the next difference should be 9 (the next odd number).
  So, 16 + 9 = 25.
  Answer: 25.

Example 52: Doubling Pattern with Subtraction

Question:
What is the next number?
2, 4, 8, 12, 16, __?

Solution:
The pattern alternates between doubling the number and subtracting 4:

• 2 × 2 = 4
• 4 + 4 = 8
• 8 × 2 = 16
• 16 + 4 = 12
  The next step will be:
  12 × 2 = 24.
  Answer: 24.

Example 53: Incrementing by Larger Numbers

Question:
What is the next number in the series?
1, 2, 4, 8, 16, __?

Solution:
The pattern doubles each number:

• 1 × 2 = 2
• 2 × 2 = 4
• 4 × 2 = 8
• 8 × 2 = 16
  So, the next number will be:
  16 × 2 = 32.
  Answer: 32.

Example 54: Consecutive Multiplication Pattern

Question:
What is the missing number?
1, 3, 9, 27, __?

Solution:
The pattern multiplies each number by 3:

• 1 × 3 = 3
• 3 × 3 = 9
• 9 × 3 = 27
  So, the next number will be:
  27 × 3 = 81.
  Answer: 81.

Example 55: Decreasing Pattern with Squares

Question:
What comes next in the series?
36, 25, 16, 9, __?

Solution:
The numbers are decreasing squares:
36 = 6²
25 = 5²
16 = 4²
9 = 3²
So, the next number is 2², which is 4.
Answer: 4.

Example 56: Adding Decreasing Integers

Question:
What is the next number in the series?
10, 15, 19, 22, __?

Solution:
The pattern involves adding consecutive integers:

• 10 + 5 = 15
• 15 + 4 = 19
• 19 + 3 = 22
  So, the next step is:
  22 + 2 = 24.
  Answer: 24.

Example 57: Alternating Addition and Multiplication

Question:
What is the next number in the sequence?
1, 3, 6, 18, 21, __?

Solution:
The pattern alternates between adding 2 and multiplying by 3:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 × 3 = 18
• 18 + 3 = 21
  The next step is:
  21 × 3 = 63.
  Answer: 63.

Example 58: Doubling then Adding

Question:
What comes next in the sequence?
2, 4, 8, 16, 32, __?

Solution:
Each number doubles the previous number:

• 2 × 2 = 4
• 4 × 2 = 8
• 8 × 2 = 16
• 16 × 2 = 32
  The next number will be:
  32 × 2 = 64.
  Answer: 64.

Example 59: Increments of 10 Pattern

Question:
What is the missing number?
10, 20, 30, 40, __?

Solution:
The pattern adds 10 to each number:

• 10 + 10 = 20
• 20 + 10 = 30
• 30 + 10 = 40
  The next number will be:
  40 + 10 = 50.
  Answer: 50.

Example 60: Exponent Pattern

Question:
What is the next number in the series?
2, 4, 8, 16, __?

Solution:
The pattern doubles each number:

• 2 × 2 = 4
• 4 × 2 = 8
• 8 × 2 = 16
  So, the next number will be:
  16 × 2 = 32.
  Answer: 32.

Example 61: Increasing by Even Numbers

Question:
What comes next in the series?
2, 6, 12, 20, __?

Solution:
The differences between consecutive numbers are increasing even numbers:

• 6 – 2 = 4
• 12 – 6 = 6
• 20 – 12 = 8
  So, the next difference should be 10.
  Thus, 20 + 10 = 30.
  Answer: 30.

Example 62: Alternating Adding and Multiplying

Question:
What is the next number in the series?
2, 4, 8, 12, 24, __?

Solution:
The pattern alternates between multiplying by 2 and adding 4:

• 2 × 2 = 4
• 4 + 4 = 8
• 8 × 2 = 16
• 16 + 4 = 20
  So, the next step is:
  20 × 2 = 40.
  Answer: 40.

Example 63: Consecutive Addition and Doubling

Question:
What comes next in the series?
1, 3, 6, 12, 20, __?

Solution:
The pattern alternates between adding an increasing integer and then doubling:

• 1 + 2 = 3
• 3 × 2 = 6
• 6 + 3 = 9
• 9 × 2 = 18
• 18 + 4 = 22
  So, the next number is 22.
  Answer: 22.

Example 64: Adding Even Numbers

Question:
What is the missing number in the series?
1, 3, 6, 10, 15, __?

Solution:
The differences between consecutive numbers are increasing by consecutive integers:

• 3 – 1 = 2
• 6 – 3 = 3
• 10 – 6 = 4
• 15 – 10 = 5
  The next difference should be 6.
  Thus, 15 + 6 = 21.
  Answer: 21.

Example 65: Multiplying by the Next Integer

Question:
What comes next in the series?
1, 2, 6, 24, 120, __?

Solution:
The pattern multiplies by increasing integers:

• 1 × 1 = 1
• 1 × 2 = 2
• 2 × 3 = 6
• 6 × 4 = 24
• 24 × 5 = 120
  So, the next number is:
  120 × 6 = 720.
  Answer: 720.

Example 66: Repeating Addition of a Number

Question:
What comes next in the series?
7, 14, 21, 28, __?

Solution:
The numbers are increasing by adding 7 to each previous number:

• 7 + 7 = 14
• 14 + 7 = 21
• 21 + 7 = 28
  So, the next number is:
  28 + 7 = 35.
  Answer: 35.

Example 67: Decreasing Pattern with Odd Numbers

Question:
What is the next number in the series?
15, 12, 9, 6, __?

Solution:
The pattern decreases by 3 each time:

• 15 – 3 = 12
• 12 – 3 = 9
• 9 – 3 = 6
  So, the next number is:
  6 – 3 = 3.
  Answer: 3.

Example 68: Fibonacci Sequence

Question:
What is the next number in the series?
1, 1, 2, 3, 5, __?

Solution:
This is a Fibonacci sequence, where each number is the sum of the previous two numbers:
1 + 1 = 2
1 + 2 = 3
2 + 3 = 5
The next number will be:
3 + 5 = 8.
Answer: 8.

Example 69: Square Numbers

Question:
What is the next number in the series?
1, 4, 9, 16, 25, __?

Solution:
The numbers are perfect squares:
1 = 1²
4 = 2²
9 = 3²
16 = 4²
25 = 5²
So, the next number is 6², which is 36.
Answer: 36.

Example 70: Dividing by Successive Integers

Question:
What comes next in the series?
100, 50, 25, 12.5, __?

Solution:
The pattern divides each number by 2:

• 100 ÷ 2 = 50
• 50 ÷ 2 = 25
• 25 ÷ 2 = 12.5
  So, the next number will be:
  12.5 ÷ 2 = 6.25.
  Answer: 6.25.

Example 71: Multiplying and Subtracting

Question:
What is the next number in the sequence?
2, 6, 12, 20, 30, __?

Solution:
The pattern is:

• 2 × 3 = 6
• 6 × 2 = 12
• 12 × 2 = 20
• 20 × 3 = 30
  So, the next number is:
  30 × 2 = 60.
  Answer: 60.

Example 72: Alternating Multiplication and Division

Question:
What comes next in the series?
10, 20, 5, 10, 2.5, __?

Solution:
The pattern alternates between multiplying by 2 and dividing by 4:

• 10 × 2 = 20
• 20 ÷ 4 = 5
• 5 × 2 = 10
• 10 ÷ 4 = 2.5
  So, the next operation will be:
  2.5 × 2 = 5.
  Answer: 5.

Example 73: Subtracting Increasing Numbers

Question:
What comes next in the sequence?
100, 90, 80, 70, __?

Solution:
The pattern subtracts 10 from each number:

• 100 – 10 = 90
• 90 – 10 = 80
• 80 – 10 = 70
  So, the next number will be:
  70 – 10 = 60.
  Answer: 60.

Example 74: Adding Increasing Multiples of 3

Question:
What is the next number in the sequence?
3, 6, 12, 21, __?

Solution:
The differences between consecutive numbers are increasing multiples of 3:

• 6 – 3 = 3
• 12 – 6 = 6
• 21 – 12 = 9
  So, the next difference should be 12:
  21 + 12 = 33.
  Answer: 33.

Example 75: Consecutive Multiplication by 2

Question:
What comes next in the sequence?
1, 2, 4, 8, __?

Solution:
Each number is multiplied by 2:

• 1 × 2 = 2
• 2 × 2 = 4
• 4 × 2 = 8
  So, the next number will be:
  8 × 2 = 16.
  Answer: 16.

Also Read : Logical reasoning question on data sufficiency

Example 76: Adding Alternating Numbers

Question:
What comes next in the series?
1, 3, 6, 8, 11, __?

Solution:
The pattern alternates between adding 2 and adding 3:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 + 2 = 8
• 8 + 3 = 11
  So, the next number will be:
  11 + 2 = 13.
  Answer: 13.

Example 77: Dividing by Powers of 2

Question:
What is the next number in the series?
64, 32, 16, 8, __?

Solution:
Each number is divided by 2:

• 64 ÷ 2 = 32
• 32 ÷ 2 = 16
• 16 ÷ 2 = 8
  So, the next number will be:
  8 ÷ 2 = 4.
  Answer: 4.

Example 78: Addition of Powers of 2

Question:
What is the missing number?
1, 3, 7, 15, __?

Solution:
The pattern adds consecutive powers of 2:

• 1 + 2 = 3
• 3 + 4 = 7
• 7 + 8 = 15
  So, the next step will be:
  15 + 16 = 31.
  Answer: 31.

Example 79: Doubling and Adding a Constant

Question:
What is the next number in the series?
1, 3, 6, 12, 24, __?

Solution:
The pattern involves doubling the number and then adding 1:

• 1 × 2 = 2, 2 + 1 = 3
• 3 × 2 = 6, 6 + 1 = 12
• 12 × 2 = 24, 24 + 1 = 48
  Thus, the next number will be:
  24 × 2 + 1 = 49.
  Answer: 49.

Example 80: Increasing Powers of 3

Question:
What comes next in the series?
3, 9, 27, 81, __?

Solution:
The pattern follows powers of 3:

• 3 = 3¹
• 9 = 3²
• 27 = 3³
• 81 = 3⁴
  So, the next number is 3⁵ = 243.
  Answer: 243.

Example 81: Alternating Adding and Multiplying

Question:
What is the next number in the sequence?
3, 6, 12, 18, 36, __?

Solution:
The pattern alternates between multiplying by 2 and adding 6:

• 3 × 2 = 6
• 6 + 6 = 12
• 12 × 2 = 24
• 24 + 6 = 30
  The next step will be:
  30 × 2 = 60.
  Answer: 60.

Example 82: Multiplying by Increasing Integers

Question:
What is the missing number in the sequence?
1, 2, 6, 24, __?

Solution:
Each number is multiplied by an increasing integer:

• 1 × 1 = 1
• 1 × 2 = 2
• 2 × 3 = 6
• 6 × 4 = 24
  So, the next number will be:
  24 × 5 = 120.
  Answer: 120.

Example 83: Adding Consecutive Numbers

Question:
What comes next in the series?
2, 5, 9, 14, __?

Solution:
The pattern adds consecutive integers:

• 2 + 3 = 5
• 5 + 4 = 9
• 9 + 5 = 14
  So, the next step is:
  14 + 6 = 20.
  Answer: 20.

Example 84: Subtracting in Decreasing Steps

Question:
What is the next number in the sequence?
30, 27, 23, 18, __?

Solution:
The pattern subtracts decreasing numbers:

• 30 – 3 = 27
• 27 – 4 = 23
• 23 – 5 = 18
  The next step will be:
  18 – 6 = 12.
  Answer: 12.

Example 85: Exponential Growth

Question:
What is the next number in the sequence?
1, 2, 4, 16, 256, __?

Solution:
Each number is raised to an increasing power of 2:

• 2⁰ = 1
• 2¹ = 2
• 2² = 4
• 2⁴ = 16
• 2⁸ = 256
  So, the next number will be:
  2¹⁶ = 65536.
  Answer: 65536.

Example 86: Alternating Addition and Subtraction

Question:
What is the next number in the series?
10, 12, 9, 11, 8, __?

Solution:
The pattern alternates between adding 2 and subtracting 3:

• 10 + 2 = 12
• 12 – 3 = 9
• 9 + 2 = 11
• 11 – 3 = 8
  The next step is:
  8 + 2 = 10.
  Answer: 10.

Example 87: Halving the Number

Question:
What is the next number in the sequence?
64, 32, 16, 8, __?

Solution:
Each number is halved:

• 64 ÷ 2 = 32
• 32 ÷ 2 = 16
• 16 ÷ 2 = 8
  So, the next number will be:
  8 ÷ 2 = 4.
  Answer: 4.

Example 88: Adding Increasing Odd Numbers

Question:
What is the missing number in the series?
1, 4, 9, 16, 25, __?

Solution:
The numbers are squares of increasing integers:

• 1 = 1²
• 4 = 2²
• 9 = 3²
• 16 = 4²
• 25 = 5²
  So, the next number will be 6², which is 36.
  Answer: 36.

Example 89: Subtracting a Constant

Question:
What is the missing number in the series?
50, 45, 40, 35, __?

Solution:
The pattern subtracts 5 from each number:

• 50 – 5 = 45
• 45 – 5 = 40
• 40 – 5 = 35
  So, the next number will be:
  35 – 5 = 30.
  Answer: 30.

Example 90: Increasing Even Numbers

Question:
What comes next in the series?
4, 8, 14, 22, __?

Solution:
The differences between consecutive numbers are increasing even numbers:

• 8 – 4 = 4
• 14 – 8 = 6
• 22 – 14 = 8
  So, the next difference should be 10:
  22 + 10 = 32.
  Answer: 32.

Example 91: Fibonacci-Like Sequence with Multiplication

Question:
What comes next in the series?
1, 2, 3, 6, 18, __?

Solution:
The pattern involves multiplying by increasing integers:

• 1 × 2 = 2
• 2 × 3 = 6
• 6 × 3 = 18
  So, the next number will be:
  18 × 3 = 54.
  Answer: 54.

Example 92: Increasing Square Numbers

Question:
What is the next number in the series?
1, 4, 9, 16, 25, __?

Solution:
These are perfect squares:
1 = 1²
4 = 2²
9 = 3²
16 = 4²
25 = 5²
So, the next number will be 6², which is 36.
Answer: 36.

Example 93: Alternating Subtraction and Division

Question:
What is the missing number in the sequence?
81, 27, 24, 12, __?

Solution:
The pattern alternates between dividing by 3 and subtracting 3:

• 81 ÷ 3 = 27
• 27 – 3 = 24
• 24 ÷ 3 = 12
  So, the next step is:
  12 – 3 = 9.
  Answer: 9.

Example 94: Incrementing Addition Pattern

Question:
What is the next number in the series?
5, 10, 16, 23, __?

Solution:
The differences between the numbers are increasing by 1:

• 10 – 5 = 5
• 16 – 10 = 6
• 23 – 16 = 7
  So, the next difference should be 8:
  23 + 8 = 31.
  Answer: 31.

Example 95: Incrementing Numbers by Multiplication

Question:
What comes next in the series?
3, 9, 27, 81, __?

Solution:
The pattern involves multiplying each number by 3:

• 3 × 3 = 9
• 9 × 3 = 27
• 27 × 3 = 81
  So, the next number will be:
  81 × 3 = 243.
  Answer: 243.

Example 96: Adding Powers of 2

Question:
What comes next in the series?
1, 3, 7, 15, __?

Solution:
The pattern adds successive powers of 2:

• 1 + 2 = 3
• 3 + 4 = 7
• 7 + 8 = 15
  So, the next number will be:
  15 + 16 = 31.
  Answer: 31.

Example 97: Alternating Addition and Subtraction

Question:
What comes next in the sequence?
5, 8, 6, 9, 7, __?

Solution:
The pattern alternates between adding 3 and subtracting 2:

• 5 + 3 = 8
• 8 – 2 = 6
• 6 + 3 = 9
• 9 – 2 = 7
  So, the next number will be:
  7 + 3 = 10.
  Answer: 10.

Example 98: Doubling and Adding

Question:
What comes next in the series?
2, 5, 10, 17, __?

Solution:
The pattern involves doubling the number and adding consecutive integers:

• 2 × 2 + 1 = 5
• 5 × 2 + 1 = 10
• 10 × 2 + 1 = 17
  So, the next step will be:
  17 × 2 + 1 = 35.
  Answer: 35.

Example 99: Subtracting Increasing Numbers

Question:
What is the next number in the sequence?
100, 95, 89, 82, __?

Solution:
The pattern subtracts increasing integers:

• 100 – 5 = 95
• 95 – 6 = 89
• 89 – 7 = 82
  So, the next step will be:
  82 – 8 = 74.
  Answer: 74.

Example 100: Addition of Powers of 3

Question:
What is the missing number in the series?
3, 6, 12, 24, 48, __?

Solution:
Each number is doubled:

• 3 × 2 = 6
• 6 × 2 = 12
• 12 × 2 = 24
• 24 × 2 = 48
  So, the next number will be:
  48 × 2 = 96.
  Answer: 96.

Example 101: Consecutive Multiples of 5

Question:
What is the next number in the series?
5, 10, 15, 20, __?

Solution:
The pattern adds 5 to each previous number:

• 5 + 5 = 10
• 10 + 5 = 15
• 15 + 5 = 20
  So, the next number will be:
  20 + 5 = 25.
  Answer: 25.

Example 102: Dividing by Increasing Powers of 2

Question:
What is the next number in the series?
64, 32, 16, 8, __?

Solution:
Each number is divided by 2:

• 64 ÷ 2 = 32
• 32 ÷ 2 = 16
• 16 ÷ 2 = 8
  So, the next number will be:
  8 ÷ 2 = 4.
  Answer: 4.

Example 103: Multiplying by Even Numbers

Question:
What comes next in the series?
2, 6, 12, 20, __?

Solution:
The pattern involves multiplying each number by the next even number:

• 2 × 2 = 6
• 6 × 2 = 12
• 12 × 2 = 20
  So, the next number will be:
  20 × 2 = 40.
  Answer: 40.

Example 104: Fibonacci-like Sequence

Question:
What comes next in the series?
1, 2, 3, 5, 8, __?

Solution:
This is a Fibonacci-like sequence, where each number is the sum of the two previous ones:

• 1 + 2 = 3
• 2 + 3 = 5
• 3 + 5 = 8
  So, the next number will be:
  5 + 8 = 13.
  Answer: 13.

Example 105: Increasing Multiples of 4

Question:
What is the missing number in the sequence?
4, 8, 12, 16, __?

Solution:
Each number is a multiple of 4:

• 4 × 1 = 4
• 4 × 2 = 8
• 4 × 3 = 12
• 4 × 4 = 16
  So, the next number will be:
  4 × 5 = 20.
  Answer: 20.

Example 106: Doubling and Adding 1

Question:
What is the missing number in the sequence?
1, 3, 7, 15, __?

Solution:
The pattern involves doubling the number and then adding 1:

• 1 × 2 + 1 = 3
• 3 × 2 + 1 = 7
• 7 × 2 + 1 = 15
  So, the next number will be:
  15 × 2 + 1 = 31.
  Answer: 31.

Example 107: Incrementing by 4

Question:
What is the next number in the sequence?
2, 6, 10, 14, __?

Solution:
The numbers are increasing by 4:

• 2 + 4 = 6
• 6 + 4 = 10
• 10 + 4 = 14
  So, the next number will be:
  14 + 4 = 18.
  Answer: 18.

Example 108: Addition of Odd Numbers

Question:
What comes next in the series?
1, 4, 9, 16, 25, __?

Solution:
These are the squares of consecutive integers:

• 1 = 1²
• 4 = 2²
• 9 = 3²
• 16 = 4²
• 25 = 5²
  So, the next number will be 6², which is 36.
  Answer: 36.

Example 109: Subtraction of Decreasing Numbers

Question:
What is the next number in the sequence?
20, 18, 15, 11, __?

Solution:
The differences are decreasing:

• 20 – 2 = 18
• 18 – 3 = 15
• 15 – 4 = 11
  So, the next step will be:
  11 – 5 = 6.
  Answer: 6.

Example 110: Multiplying by 3

Question:
What comes next in the series?
3, 9, 27, 81, __?

Solution:
Each number is multiplied by 3:

• 3 × 3 = 9
• 9 × 3 = 27
• 27 × 3 = 81
  So, the next number will be:
  81 × 3 = 243.
  Answer: 243.

Example 111: Adding Increasing Numbers

Question:
What is the next number in the sequence?
2, 4, 7, 11, __?

Solution:
The pattern adds consecutive integers:

• 2 + 2 = 4
• 4 + 3 = 7
• 7 + 4 = 11
  So, the next step will be:
  11 + 5 = 16.
  Answer: 16.

Example 112: Alternating Between Addition and Multiplication

Question:
What comes next in the series?
1, 4, 12, 48, __?

Solution:
The pattern alternates between multiplying by 4 and adding 1:

• 1 × 4 = 4
• 4 + 1 = 5
• 5 × 4 = 20
• 20 + 1 = 21
  So, the next number will be:
  21 × 4 = 84.
  Answer: 84.

Example 113: Adding Consecutive Even Numbers

Question:
What is the next number in the sequence?
2, 6, 12, 20, __?

Solution:
The pattern adds consecutive even numbers:

• 2 + 4 = 6
• 6 + 6 = 12
• 12 + 8 = 20
  So, the next number will be:
  20 + 10 = 30.
  Answer: 30.

Example 114: Exponentiation of 2

Question:
What is the next number in the sequence?
2, 4, 8, 16, __?

Solution:
Each number is a power of 2:

• 2 = 2¹
• 4 = 2²
• 8 = 2³
• 16 = 2⁴
  So, the next number will be 2⁵ = 32.
  Answer: 32.

Example 115: Subtracting Decreasing Numbers

Question:
What is the next number in the series?
50, 48, 45, 41, __?

Solution:
The differences are decreasing:

• 50 – 2 = 48
• 48 – 3 = 45
• 45 – 4 = 41
  So, the next step will be:
  41 – 5 = 36.
  Answer: 36.

Example 116: Multiplying by Increasing Factors

Question:
What is the missing number in the sequence?
2, 6, 24, 120, __?

Solution:
The pattern involves multiplying by increasing integers:

• 2 × 1 = 6
• 6 × 2 = 24
• 24 × 3 = 120
  So, the next number will be:
  120 × 4 = 480.
  Answer: 480.

Example 117: Adding a Constant

Question:
What is the next number in the series?
3, 6, 9, 12, __?

Solution:
The pattern adds 3 to each previous number:

• 3 + 3 = 6
• 6 + 3 = 9
• 9 + 3 = 12
  So, the next number will be:
  12 + 3 = 15.
  Answer: 15.

Example 118: Alternating Addition and Multiplication

Question:
What is the next number in the series?
5, 10, 15, 30, __?

Solution:
The pattern alternates between adding 5 and multiplying by 2:

• 5 + 5 = 10
• 10 + 5 = 15
• 15 × 2 = 30
  So, the next number will be:
  30 + 5 = 35.
  Answer: 35.

Example 119: Powers of 3

Question:
What is the next number in the sequence?
3, 9, 27, 81, __?

Solution:
Each number is a power of 3:

• 3 = 3¹
• 9 = 3²
• 27 = 3³
• 81 = 3⁴
  So, the next number will be 3⁵ = 243.
  Answer: 243.

Example 120: Subtracting Successive Integers

Question:
What is the next number in the series?
10, 9, 7, 4, __?

Solution:
The pattern subtracts successive integers:

• 10 – 1 = 9
• 9 – 2 = 7
• 7 – 3 = 4
  So, the next step will be:
  4 – 4 = 0.
  Answer: 0.

Example 121: Adding Increasing Powers of 2

Question:
What comes next in the sequence?
1, 3, 7, 15, __?

Solution:
The numbers follow a pattern of adding powers of 2:

• 1 + 2 = 3
• 3 + 4 = 7
• 7 + 8 = 15
  So, the next number will be:
  15 + 16 = 31.
  Answer: 31.

Example 122: Fibonacci-like Sequence with Doubling

Question:
What is the next number in the sequence?
1, 2, 4, 8, 16, __?

Solution:
The numbers are doubling each time:

• 1 × 2 = 2
• 2 × 2 = 4
• 4 × 2 = 8
• 8 × 2 = 16
  So, the next number will be:
  16 × 2 = 32.
  Answer: 32.

Example 123: Adding a Constant Difference

Question:
What comes next in the series?
100, 95, 90, 85, __?

Solution:
The pattern subtracts 5 from each number:

• 100 – 5 = 95
• 95 – 5 = 90
• 90 – 5 = 85
  So, the next number will be:
  85 – 5 = 80.
  Answer: 80.

Example 124: Increasing Differences

Question:
What is the next number in the sequence?
1, 3, 6, 10, 15, __?

Solution:
The differences between the numbers are increasing:

• 3 – 1 = 2
• 6 – 3 = 3
• 10 – 6 = 4
• 15 – 10 = 5
  So, the next difference will be 6:
  15 + 6 = 21.
  Answer: 21.

Example 125: Multiplying by Successive Integers

Question:
What is the next number in the sequence?
2, 4, 8, 16, __?

Solution:
Each number is multiplied by 2:

• 2 × 2 = 4
• 4 × 2 = 8
• 8 × 2 = 16
  So, the next number will be:
  16 × 2 = 32.
  Answer: 32.

Example 126: Alternating Subtraction and Multiplication

Question:
What is the next number in the series?
10, 20, 19, 38, __?

Solution:
The pattern alternates between adding and subtracting:

• 10 × 2 = 20
• 20 – 1 = 19
• 19 × 2 = 38
  So, the next step will be:
  38 – 1 = 37.
  Answer: 37.

Example 127: Exponentiation Sequence

Question:
What is the next number in the series?
1, 2, 4, 16, 256, __?

Solution:
Each number is raised to the power of 2:

• 2⁰ = 1
• 2¹ = 2
• 2² = 4
• 2⁴ = 16
• 2⁸ = 256
  So, the next number will be:
  2¹⁶ = 65536.
  Answer: 65536.

Example 128: Successive Powers of 2

Question:
What is the next number in the sequence?
1, 2, 4, 8, 16, __?

Solution:
The pattern is powers of 2:

• 2⁰ = 1
• 2¹ = 2
• 2² = 4
• 2³ = 8
• 2⁴ = 16
  So, the next number will be 2⁵ = 32.
  Answer: 32.

Example 129: Subtracting Successive Multiples

Question:
What comes next in the sequence?
100, 90, 70, 40, __?

Solution:
The differences are decreasing in multiples of 10:

• 100 – 10 = 90
• 90 – 20 = 70
• 70 – 30 = 40
  So, the next step will be:
  40 – 40 = 0.
  Answer: 0.

Example 130: Incremental Addition

Question:
What is the next number in the series?
1, 3, 6, 10, 15, __?

Solution:
The pattern involves adding consecutive integers:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 + 4 = 10
• 10 + 5 = 15
  So, the next number will be:
  15 + 6 = 21.
  Answer: 21.

Example 131: Powers of 2 Minus 1

Question:
What comes next in the sequence?
1, 3, 7, 15, 31, __?

Solution:
Each number is one less than a power of 2:

• 2¹ – 1 = 1
• 2² – 1 = 3
• 2³ – 1 = 7
• 2⁴ – 1 = 15
• 2⁵ – 1 = 31
  So, the next number will be:
  2⁶ – 1 = 63.
  Answer: 63.

Example 132: Increasing Squares

Question:
What comes next in the sequence?
1, 4, 9, 16, 25, __?

Solution:
These are the squares of consecutive integers:

• 1 = 1²
• 4 = 2²
• 9 = 3²
• 16 = 4²
• 25 = 5²
  So, the next number will be 6² = 36.
  Answer: 36.

Example 133: Doubling and Adding

Question:
What comes next in the sequence?
1, 4, 11, 22, __?

Solution:
The pattern involves doubling the number and adding 2:

• 1 × 2 + 2 = 4
• 4 × 2 + 3 = 11
• 11 × 2 + 4 = 22
  So, the next number will be:
  22 × 2 + 5 = 49.
  Answer: 49.

Example 134: Adding Consecutive Odd Numbers

Question:
What is the next number in the sequence?
1, 3, 6, 10, 15, __?

Solution:
The differences between the numbers are consecutive odd numbers:

• 1 + 2 = 3
• 3 + 3 = 6
• 6 + 4 = 10
• 10 + 5 = 15
  So, the next number will be:
  15 + 6 = 21.
  Answer: 21.

Example 135: Multiplying by 2 and Adding 1

Question:
What comes next in the sequence?
1, 3, 7, 15, 31, __?

Solution:
Each number is doubled and then increased by 1:

• 1 × 2 + 1 = 3
• 3 × 2 + 1 = 7
• 7 × 2 + 1 = 15
• 15 × 2 + 1 = 31
  So, the next number will be:
  31 × 2 + 1 = 63.
  Answer: 63.

Example 136: Decreasing Multiples of 5

Question:
What is the next number in the sequence?
50, 45, 40, 35, __?

Solution:
The pattern subtracts 5 from each number:

• 50 – 5 = 45
• 45 – 5 = 40
• 40 – 5 = 35
  So, the next number will be:
  35 – 5 = 30.
  Answer: 30.

Example 137: Multiplying by Consecutive Integers

Question:
What is the next number in the sequence?
1, 2, 6, 24, 120, __?

Solution:
Each number is multiplied by the next integer:

• 1 × 1 = 1
• 1 × 2 = 2
• 2 × 3 = 6
• 6 × 4 = 24
• 24 × 5 = 120
  So, the next number will be:
  120 × 6 = 720.
  Answer: 720.

Example 138: Alternating Addition and Subtraction

Question:
What is the next number in the sequence?
1, 4, 2, 5, 3, __?

Solution:
The pattern alternates between adding 3 and subtracting 2:

• 1 + 3 = 4
• 4 – 2 = 2
• 2 + 3 = 5
• 5 – 2 = 3
  So, the next number will be:
  3 + 3 = 6.
  Answer: 6.

Example 139: Adding Consecutive Even Numbers

Question:
What comes next in the series?
2, 6, 12, 20, __?

Solution:
The pattern adds consecutive even numbers:

• 2 + 4 = 6
• 6 + 6 = 12
• 12 + 8 = 20
  So, the next number will be:
  20 + 10 = 30.
  Answer: 30.

Example 140: Dividing by Successive Numbers

Question:
What is the next number in the sequence?
64, 32, 16, 8, __?

Solution:
Each number is divided by 2:

• 64 ÷ 2 = 32
• 32 ÷ 2 = 16
• 16 ÷ 2 = 8
  So, the next number will be:
  8 ÷ 2 = 4.
  Answer: 4.

Example 141: Increasing by 4

Question:
What comes next in the series?
2, 6, 10, 14, __?

Solution:
The pattern adds 4 to each previous number:

• 2 + 4 = 6
• 6 + 4 = 10
• 10 + 4 = 14
  So, the next number will be:
  14 + 4 = 18.
  Answer: 18.

Example 142: Fibonacci-like Sequence

Question:
What comes next in the series?
2, 4, 6, 10, 16, __?

Solution:
The pattern involves adding the previous two numbers:

• 2 + 4 = 6
• 4 + 6 = 10
• 6 + 10 = 16
  So, the next number will be:
  10 + 16 = 26.
  Answer: 26.

Example 143: Multiplying by Powers of 3

Question:
What is the next number in the sequence?
3, 9, 27, 81, __?

Solution:
Each number is multiplied by 3:

• 3 × 3 = 9
• 9 × 3 = 27
• 27 × 3 = 81
  So, the next number will be:
  81 × 3 = 243.
  Answer: 243.

Example 144: Successive Addition of Primes

Question:
What comes next in the sequence?
2, 5, 10, 17, __?

Solution:
The pattern adds consecutive prime numbers:

• 2 + 3 = 5
• 5 + 5 = 10
• 10 + 7 = 17
  So, the next number will be:
  17 + 11 = 28.
  Answer: 28.

Example 145: Multiplying by 4

Question:
What is the next number in the series?
1, 4, 16, 64, __?

Solution:
Each number is multiplied by 4:

• 1 × 4 = 4
• 4 × 4 = 16
• 16 × 4 = 64
  So, the next number will be:
  64 × 4 = 256.
  Answer: 256.

Example 146: Subtracting Successive Multiples

Question:
What is the next number in the sequence?
100, 95, 90, 85, __?

Solution:
The pattern subtracts 5 from each number:

• 100 – 5 = 95
• 95 – 5 = 90
• 90 – 5 = 85
  So, the next number will be:
  85 – 5 = 80.
  Answer: 80.

Example 147: Increasing Powers of 3

Question:
What is the next number in the sequence?
3, 9, 27, 81, __?

Solution:
The pattern multiplies each number by 3:

• 3 × 3 = 9
• 9 × 3 = 27
• 27 × 3 = 81
  So, the next number will be:
  81 × 3 = 243.
  Answer: 243.

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