Question

Find the smallest number by which the following number must be divided to obtain a perfect cube.

81

• A. 3
• B. 6
• C. 7
• D. 14

Answer 1

The correct option is A 3

Writing 81 as a product of prime factors, we have
$81=\underset{–}{3\times 3\times 3}\times 3$
Clearly, to make it a perfect cube, it must be divided by 3.