Question

Which number will replace the question mark (?) in the following series:

25, 216, 49, 512, ?

1. 81
2. 729
3. 625
4. 64

Answer 1

Correct Answer - Option 1 : 81

The pattern follows here is:

The series are in the form of alternate squares and cubes. 

25 = 5²

216 = 6³

49 = 7²

512 = 8³

? = 9²

? = 81 

Hence, the correct answer is "81".