Question

If a number is multiplied by 5, then the cube of the new number will become _____ times the cube of the original number.

• A. 1
• B. 9
• C. 64
• D. 125

Answer 1

The correct option is D 125

Let us consider the number as '$a$'
So, cube of '$a$' = $a^3$...............(1)
Now, the number is multipled by 5.
$\therefore$ New number = $5a$
Cube of new number $=(5a{)}^3$
$=125a^3$..........(2)
From, (1) and (2) it can be said that the cube of the new number is 125 times the cube of the original number.