Which of the following number sets is different from the others?
(9, 18, 36)
(12, 24, 48)
(7, 14, 29)
(5, 10, 20)

The correct option is (7, 14, 29).

Step-by-step Explanation:

Let us analyze the relationship between the numbers in each of the given sets to find the underlying pattern.

In a standard set of three numbers (a, b, c), let us check the ratio or multiplier between consecutive terms:

1. First set: (9, 18, 36)

The second number is obtained by doubling the first number:

$9\times 2=18$

The third number is obtained by doubling the second number:

$18\times 2=36$

Pattern followed: Each subsequent number is twice the previous number.

2. Second set: (12, 24, 48)

The second number is obtained by doubling the first number:

$12\times 2=24$

The third number is obtained by doubling the second number:

$24\times 2=48$

Pattern followed: Each subsequent number is twice the previous number.

3. Fourth set: (5, 10, 20)

The second number is obtained by doubling the first number:

$5\times 2=10$

The third number is obtained by doubling the second number:

$10\times 2=20$

Pattern followed: Each subsequent number is twice the previous number.

4. Third set: (7, 14, 29)

The second number is obtained by doubling the first number:

$7\times 2=14$

However, when we double the second number:

$14\times 2=28\ne 29$

Instead of 28, the third term given in this set is 29.

Conclusion:

All sets except (7, 14, 29) follow the rule where each number is multiplied by 2 to get the next number in the sequence. Therefore, (7, 14, 29) is different from the others.