Question

A solid cube of edge 28 cm is melted down and recasted into smaller cubes of edge length 4 cm. Find the number of smaller cubes obtained.

• A. 343
• B. 356
• C. 368
• D. 396

Answer 1

The correct option is A 343

Given:
Edge of cube before melting = 28 cm.
Edge of 1 smaller cube after melting = 4 cm.

We know that,
volume of cube
= $(\text{edge}{)}^3$
$\therefore$ volume of cube before melting
= $(28{)}^3=21,952c{m}^3$
And volume of smaller cube
= $(4{)}^3=64c{m}^3$
Number of smaller cubes obtained $=\frac{\text{volume of cube before melting}}{\text{volume of smaller cube}}$
$=\frac{21952}{64}$
= 343
Therefore, 343 cubes will be obtained.