The radius of the base and the height of a closed cylinder are 14 cm and 14 cm, respectively. The total surface area of the cylinder is equal to the area of a circle. What will be the diameter of the circle? [Use $$\pi = \frac{22}{7}$$]

The radius of the base and the height of a closed cylinder are 14 cm and 14 cm, respectively.

Let's assume the radius of the base and the height of a closed cylinder and 'r' and 'h' respectively.

Let's assume the radius of the circle is 'R'.

The total surface area of the cylinder is equal to the area of a circle.

$$2\times\ \pi\ \times\ r\times\ \left(r+h\right)\ =\ \pi\ \times\ R^2$$

$$2\times\ 14\times\ \left(14+14\right)\ =\ R^2$$

$$28\times28\ =\ R^2$$

$$28^2\ =\ R^2$$

Diameter of the circle = 2R

= $$2\times28$$

= 56 cm