Question

A cube of 4 cm has been painted on its surface in such a way that two opposite surfaces have been painted blue and two adjacent surfaces have been painted red Two remaining surfaces have been left unpainted Now the cube is cut into smaller cubes of sides 1 cm each

How many cubes will have at least blue colour on its surface?

• A. 20
• B. 8
• C. 24
• D. 32

Answer 1

The correct option is D 32

Number of cubes with at least blue colour on its surface = Number of cubes present at 2 blue surface
$=2\times n^2=2\times 4^2-4=32$
Here n = $\frac{sideofbigcube}{sideofsmallcube}=\frac{4}{1}=4$