Question

find the smallest number by which the following must be multiplied to make them the perfect cube 2560​

Answer 1

Take Prime factors of 2560.

2560 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 5.

The product has 3 set of 23 and a 5.

Clearly, to make it a perfect cube, it must be multiplied by 5 x 5 i.e. 25.