Question

Find the smallest no. by which each of the following no. must be divided to obtain a perfect cube.
(i) $81$
(ii) $128$
(iii) $135$
(iv) $192$
(v) $704$

Answer 1

(i) $81=3\times 3\times 3\times 3=$ $3^3\times 3$
Rquired no. $=3$
(ii) $128=$ $2^3\times 2^3\times 2$
Required no. $=2$
(iii) $135=$ $3^3\times 5$
Required no. $=5$
(iv) $192=$ $2^3\times 2^3\times 3$
Required no.$=3$
(v) $704=$ $2^3\times 2^3\times 11$
Required no. $=11$