Which of the following numbers is not a perfect square? 24 25 64 100

Hi! 

A perfect square is the product of when a whole number is multiplied by itself

Ex:

6 × 6 = 36, 36 is the perfect square. 

The number that is being multiplied is the square root. 

So to find the correct answer for this question, let's use the process of elimination. 

100 = 10 × 10 so we can cross out 100

64 = 8 × 8 so we can cross out 64

25 = 5 × 5 so we can cross out 25

Now all we have left is 24, which is not a perfect square. 

A. 24

Hope this helps :)