If a cuboid of dimensions 32 cm ×12 cm × 9 cm is cut into two cubes of same size, what will be the ratio of the surface area of the cuboid to the total surface area of the two cubes?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 ie 65 : 72
Explanation:
32 cm ×12 cm × 9 cm = 2 × a3
a3 = (32 ×12 × 9) / 2
a3 = 123
a = 12
T.S.A. of the cube = 12 × a2
= 12 ×12 × 12 = 144
T.S.A. of cuboid = 2[(32 × 9) + (9 × 12) + (12 × 32)]
= 2[(32 × 9) + (9 × 12) + (12 × 32)]/12³
= 130/144 = 65/72