The ratio of radii of $2$ right circular cylinders is $2:3$ and their heights are in the ratio $5:4$. The ratio of their curved surface area is

The diagonal of a cubical box is $\sqrt{300} \text{ cm}$. Find out the surface area.

The capacity of a tank,in the form of a cylinder,is $6160 \, m^3$. If the diameter of its base is $28 \, m$,find out the cost of painting its inner curved surface at the rate of ₹ $2.8$ per $m^2$. (Use $\pi = \frac{22}{7}$)

$A$ large solid sphere is melted and moulded to form identical right circular cones with base radius and height same as the radius of the sphere. One of these cones is melted and moulded to form a smaller solid sphere. Then the ratio of the surface area of the smaller to the surface area of the larger sphere is

The number of coins,each of radius $0.75\, cm$ and thickness $0.2\, cm$,to be melted to make a right circular cylinder of height $8\, cm$ and radius $3\, cm$ is:

How many small cubes,each of $96\,cm^{2}$ surface area,can be formed from the material obtained by melting a larger cube with $384\,cm^{2}$ surface area?