The total surface area of a hemisphere is 462 cm$$^2$$. What is its diameter?(Take $$\pi = \frac{22}{7}$$)

The total surface area of a hemisphere is 462 cm$$^2$$.

total surface area of a hemisphere = 462

$$3\times\ \pi\ \times\ \left(radius\right)^2 = 462$$

$$3\times\ \frac{22}{7}\times\ \left(radius\right)^2=462$$

$$\frac{22}{7}\times\ \left(radius\right)^2=154$$

$$\frac{1}{7}\times (radius)^2=7$$

$$(radius)^2=7^2$$

radius of a hemisphere = 7 cm

Diameter of a hemisphere = 2$$ \times$$ radius of a hemisphere

= $$2\times7$$

= 14 cm