In the number series 10, 13, 19, 28, 40, the next term is _______. – UGC NET Question

The differences between the terms are 3, 6, 9 and 12. These differences form a simple arithmetic progression where each difference increases by 3. Following this logic, the next difference should be 15. Adding 15 to the last term 40 gives 55, which continues the pattern in a consistent manner.

Option A:
Option A yields 55, which is 15 greater than 40 and extends the difference sequence to 3, 6, 9, 12, 15. This smooth increase by 3 at the second level is exactly what the pattern suggests. Therefore, 55 is the correct next term in the series.

Option B:
Option B gives 53, which corresponds to a difference of 13 and does not match the expected multiple of 3. This breaks the uniform pattern of the differences. Hence, 53 cannot be considered correct.

Option C:
Option C suggests 57, which would produce a difference of 17 from 40, again not a multiple of 3 and out of step with the existing sequence of differences. Thus, 57 is not consistent with the pattern.

Option D:
Option D offers 60, which is 20 more than 40 and introduces a much larger difference than the expected 15. This disrupts the clear second-level arithmetic structure and makes the series irregular. Therefore, 60 is not an appropriate continuation.