Question

A cube of edge 5 cm is cut into cubes each of edge of 1 cm. The ratio of the total surface area of one of the small cubes to that of the large cube is equal to :

• A. 1 : 125
• B. 1 : 5
• C. 1 : 625
• D. 1 : 25

Answer 1

Answer:

D. 1 : 25

Surface area of a small cube =6 × (edge)² = 6 × 1 = 6 cm²

Surface area of the large cube = 6 (5)² = 6 × 25 cm².

Required ratio $=\frac{6}{6\times{25}}=\frac{1}{25}$

or 1 : 25