Question

A large cube is formed by melting three smaller cubes with sides 3,4 and 5 cm. What is the ratios of total surface area

Answer 1

TSA OF smaller cubes of edges 3 ;4;5are 54;96;150 respectively.
so the TSA of bigger cube =6a^2
ratio smaller cubes =54/96=9:16
similarly ratio of 96/150=25:16
then ratio of smaller cube is 9:16:25