The sides of three cubes are 3 cm, 4 m and 5 cm respectively. The side

1.	The sides of three cubes are 3 cm, 4 m and 5 cm respectively. The side of the cube which recasted by the melting three cubes is:(A) 6 cm(B) 5 cm(C) 7 cm(D) 4 cm
Answer» Answer is (A) 6 cm Volume of I^st cube = (3)³ = 27 cm³ Volume of II^nd cube (4)³ = 64 cm³ Volume of III^rd cube = (5)³ = 125 cm³ Sum of the volumes of these three cubes = 27 + 64 + 125 = 216 cm³ Now cube is recasted with these three cubes. ∴ Volume of the cubes recasted = Sum of the volumes of three cubes. (core)³ = 216 core = \(\sqrt [ 3 ]{ 216 }\) = \(\sqrt [ 3 ]{ 6\times 6\times 6 } \) = 6 cm

The sides of three cubes are 3 cm, 4 m and 5 cm respectively. The side of the cube which recasted by the melting three cubes is:(A) 6 cm(B) 5 cm(C) 7 cm(D) 4 cm

Answer»

Answer is (A) 6 cm

Volume of I^st cube = (3)³ = 27 cm³

Volume of II^nd cube (4)³ = 64 cm³

Volume of III^rd cube = (5)³ = 125 cm³

Sum of the volumes of these three cubes

= 27 + 64 + 125 = 216 cm³

Now cube is recasted with these three cubes.

∴ Volume of the cubes recasted

= Sum of the volumes of three cubes.

(core)³ = 216

core = \(\sqrt [ 3 ]{ 216 }\)

= \(\sqrt [ 3 ]{ 6\times 6\times 6 } \) = 6 cm