Question

If the unit digit of a number is 3. What is the unit digit of its cube?

• A. 1
• B. 3
• C. 7
• D. 9

Answer 1

The correct option is C 7

If the unit digit of a number is 3 then its cube will have 7 in its unit digit and vice versa.
Ex:
${\underset{–}{3}}^3=2\underset{–}{7}$
$1{\underset{–}{3}}^3=13\times 13\times 13=219\underset{–}{7}$