Question

6. Radius of a spherical balloon increases from 8cm to 12 cm. the
ratio of the surface areas of balloon in two cases is
02:3
o 3:2
08:27
04:9​

Answer 1

Answer :

• The ratio of the surface areas of balloon in two cases is 4 : 9

Given :

• Radius of a spherical balloon increases from 8cm to 12cm

To find :

• Ratio of the surface area of balloon in two cases is

Solution :

• Let the radius of smaller balloon be r₁ = 8cm
• Let the radius of larger balloon be r₂ = 12cm

As we know that,

Balloon is like a sphere

• Surface area of Balloon = 4πr²

So , now we have to find the ratio of the surface areas of balloon in two cases

》4πr₁² /4πr₂²

》r₁ ²/r₂²

》(8)²/(12)²

》8 × 8 / 12 × 12

》4/9

Hence , The ratio of the surface areas of balloon in two cases is 4 : 9