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A cube of side 8 cm is painted red on all the sides. It is then cut into smaller cubes, each of side 2 cm. How many of these smaller cubes have one or more sides painted red?

A cube of side 8 cm is painted red on all the sides. It is then cut into smaller cubes, each of side 2 cm. How many of these smaller cubes have one or more sides painted red? Correct Answer 56

Cubes with paints on 3 sides = 8 cubes ( 8 corners)

Cubes with paint on 2 sides = 24

(8 cubes on each side but these 8 are shared by two faces so 8 × 3 = 24)

Cubes with paint on 1 side = 24 (4 cubes on each face. 4 × 6 = 24)

Total = 24 + 24 + 8 = 56.

Hence, 56 is the correct answer. 

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