Exercise

Surface area of a cube $=4\times ($side${)}^2$

The surface area of this prism in the first box below equals to the sum of the surface areas of the two cuboids in the second box below.

If the surface area of a sphere is $616 {\mathrm{cm}}^2$, its diameter (in $\mathrm{cm}$) is 

The total surface area of a cube is $864 {\mathrm{cm}}^2$. Its volume is

The number of solid spheres, each of diameter $6 \mathrm{cm}$, that can be made by melting a solid metal cylinder of height $45 \mathrm{cm}$ and diameter $4 \mathrm{cm}$, is 

The ratio of the volume of a cone and a cylinder of equal diameters and equal heights is

A solid cylinder of radius $r$ and height $h$ is placed over the cylinder of same height and radius. The total surface area of the shape so formed is $4\mathrm{\pi }rh+4\mathrm{\pi }{r}^2.$

A cubical box has each edge $10 \mathrm{c}\mathrm{m}$ and another cuboidal box is $12.5 \mathrm{c}\mathrm{m}$ long, $10 \mathrm{c}\mathrm{m}$ wide and $8 \mathrm{c}\mathrm{m}$ high. Which box has the smaller total surface area and by how much?