Question

Question 18

Write the correct answer from the given four options.

Which of the following numbers is not a perfect cube?

a) 216
b) 567
c) 125
d) 343

Answer 1

$216=6\times 6\times 6,567=3\times 3\times 3\times 3\times 7$
$125=5\times 5\times 5,343=7\times 7\times 7$
Clearly, 567 is not a perfect cube, because in grouping, the factors in triplets of equal factors, we are left with two factors $3\times 7$