Multiple choice

A number series is given below, in which only one number is wrong. Find out the wrong number. 17, 35, 57, 80, 105, 132, 161, 192

  1. 105

  2. 80

  3. 57

  4. 35

  5. 17
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The differences between consecutive terms in the series are 18, 22, 23, 25, 27, 29, and 31. The differences from the third term onward (23, 25, 27, 29, 31) form a sequence of consecutive odd numbers. Extending this pattern backward, the first two differences should be 19 and 21 instead of 18 and 22, which means the second term should be 17 + 19 = 36 instead of 35.

AI explanation

The differences between the consecutive terms of the series are multiples of 11. The differences start at 22, then go to 33, 44, 55, 66, 77, and 88, but 35 minus 17 gives 18 instead of 22. Therefore, 35 is the wrong number in the series.

Keep practicing — related questions