A closed box made of wood of uniform thickness has length, breadth and height 12 cm, 10 cm and 8 cm respectively. If the thickness of the wood is 1 cm, the inner surface area is :

A. 264 cm²

B. 376 cm²

C. 456 cm²

D. 696 cm²

Answer: Option B

Solution(By Examveda Team)

Internal length = (12 - 2) cm = 10 cm
Internal breadth = (10 - 2) cm = 8 cm
Internal height = (8 - 2) cm = 6 cm
Inner surface area :
= 2 [10 × 8 + 8 × 6 + 10 × 6] cm²
= (2 × 188) cm²
= 376 cm²