Question

the radius of spherical balloon increases from 8 to 12 cm what is the ratio of the surface areas of the balloon into cases

Answer 1

64/144

=32/72

=16/36

=8/18

2/9

ans= 2:9

Answer 2

Given :

The radius of spherical balloon increases from 8 to 12 cm

To Find :

what is the ratio of the surface areas of the balloon

Solution:

Radius of spherical balloon = 8 cm

Surface area of balloon = $4 \pi r^2 = 4 \times \frac{22}{7} \times 8^2$

We are given that the radius of spherical balloon increases from 8 to 12 cm

So, New radius = 12 cm

Surface area of balloon =$4 \pi r^2 = 4 \times \frac{22}{7} \times 12^2$

Ratio of the surface areas of the balloon = $\frac{8^2}{12^2}$

Ratio of the surface areas of the balloon =$\frac{4}{9}$

Hence the ratio of the surface areas of the balloon is 4:9