A large cube is formed from the material obtained by melting three sm…

Question

A large cube is formed from the material obtained by melting three smaller cubes of 3, 4 and 5 cm side. What is the ratio of the total surface areas of the smaller cubes and the large cube?

Accepted Answer

Option C. 25 : 18. Answer & Solution Answer: Option C Solution: & Volume\, of\, the\, large\, cube & = ( 3^3 + 4^3 + 5^3 ) = 216\,cm^3 & Let\, the\, edge\, of\, the\, large\, cube\, be\,a & So,\,a^3 = 216\,\,\,\,\, \,\,\,\,\,a = 6\,cm & Required\, ratio & = 6 × ( 3^2 + 4^2 + 5^2 )6 × 6^2 & = 5036…