Odd man out and series

(1) Look at this series: 2, 4, 8, 16, 32, 64, …, What number should fill the blank?

• (a) 100
• (b) 90
• (c) 128
• (d) 256

Answer

Correct Answer: (c) 128
This is a simple doubling series; each number is twice the previous number.
2, 2 \times 2, 2^3, 2^4, 2^5, 2^6, \ldots
The next number is \( 2^7 = 128 \).

(2) Which of the following numbers does not belong in the series: 1, 2, 5, 10, 13, 26, 29, 48?

• (a) 1
• (b) 48
• (c) 29
• (d) 13

Answer

Correct Answer: (b) 48
The pattern is adding 1, then multiplying by 2, then adding 1, and so on.
1, 1+1, 2 \times 2, 4+1, 5 \times 2, 10+3, 13 \times 2, \ldots
The correct number should be \( 29 \times 2 = 58 \), not 48.

(3) Look at this series: 7, 10, 8, 11, 9, 12, …, What number should fill the blank?

• (a) 10
• (b) 7
• (c) 12
• (d) 15

Answer

Correct Answer: (a) 10
The series alternates between adding 3 and subtracting 2.
7, 7+3, 10-2, 8+3, 11-2, \ldots
The next number should be \( 9+1 = 10 \).

ChatGPT
Certainly! Here are the next 7 questions for “Odd Man Out and Series” with their answers and explanations:

(4) Which number does not belong in the series: 3, 9, 27, 36, 81, 108, 243?

• (a) 3
• (b) 36
• (c) 108
• (d) 243

Answer

Correct Answer: (b) 36
This is a series of cubes of consecutive odd numbers: 1^3, 3^3, 5^3, 7^3, 9^3, \ldots
The number 36 does not follow this pattern.

(5) Look at this series: 21, 23, 28, 30, 35, 37, … What number should fill the blank?

• (a) 40
• (b) 39
• (c) 42
• (d) 38

Answer

Correct Answer: (c) 42
This is an alternating series with a pattern of adding 2 and then adding 5.
21+2, 23+5, 28+2, 30+5, 35+2, \ldots
The next number should be \( 37+5 = 42 \).