Question:
Three metallic solid cubes whose edges are 3 cm, 4 cm and 5 cm are melted and formed into a single cube. Find the edge of the cube so formed.
Solution:
Given, edges of three solid cubes are 3 cm, 4 cm and 5 cm, respectively.
∴ Volume of first cube = (3)3 = 27 cm3
Volume of second cube = (4)3 = 64 cm3
and volume of third cube = (5)3 = 125 cm3
∴ Sum of volume of three cubes = (27 + 64 + 125) = 216 cm3
Let the edge of the resulting cube = R cm
Then, volume of the resulting cube, R3 =216 ⇒ R = 6cm