Question

If surface area of two hemisphere are in the ratio 25:49, find the ratio of their radii

Answer 1

Hey Friend,

Let the radius of first hemisphere be 'r' units
Let the radius of second hemisphere be 'R' units

therefore,

2 x $\pi$ x r^2  /  2 x $\pi$ x R^2 = 25 / 49
r^2 / R^2 = 25 / 49
r / R = 5 / 7

Therefore, the ratio of radii is 5:7.

Hope it helps!

Answer 2

Given:

Ratio of surface area of two hemisphere is 25:49.

To Find:

The ratio of their radius?

Step-by-step explanation:

• Let the radius if one hemisphere is r then its surface area will be $2\pi r^2$

• Let the radius if other hemisphere is $r_2$ then its surface area will be $2\pi r_2^2$

• Now given ratio of their surface area is 25:49

                  $\Rightarrow \frac{2\pi r^2}{2\pi r_2^2} =\frac{25}{49}$

    0N solving above equation        

                      $\frac{r^2}{r_2^2} =\frac{25}{49} \\\frac{r}{r_2} =\frac{5}{7}$

Thus, ratio of their radius is 5:7