4 questions of Mensuration

1. The ratio of the sides of two cubes is 2:5. If the surface area of the larger cube is 600cm2, what is the surface area of the smaller cube?
Ans = 600*(2/5)^2 = 96cm^2



2. The cost of painting the outer surface of cylindrical container A is $80. If the radius of a similar container B is 3 times that of container A, what is the cost of painting the outer surface of container B?
Ans = $80*3^2 = $720

3. A metallic sphere of radius 9 cm is melted. How many metallic spheres of radii 3 cm can be recast?
Ans = (9/3)^3 = 27


4.The ratio of the volumes of two similar pyramids is 8:27. What is the ratio of their surface areas?
Ans = (8/27)^(2/3) = 4:9