Question

Write the ones digit of the cube of each of the following numbers

A) $231$

B) $358$

C) $491$

D) $854$

E) $987$

F) $752$

Answer 1

Multiply one's digit

$(231{)}^3=231\times 231\times 231$

$\Rightarrow$ One's digit $=1\times 1\times 1=1$

$(358{)}^2=8\times 8\times 8=512$

$\Rightarrow$ One's digit $=2$

$(491{)}^3=1\times 1\times 1=1$

$(854{)}^3=4\times 4\times 4=64$

$\Rightarrow$ One's digit $=4$

$(987{)}^3=7\times 7\times 7=343$

$\Rightarrow$ One's digit $=3$

$(752{)}^3=2\times 2\times 2=8$