# Telangana SCERT Class 9 Math Solution Chapter 10 Surface Areas and Volumes Exercise 10.4

## Telangana SCERT Solution Class IX (9) Math Chapter 10 Surface Areas and Volumes Exercise 10.4

(1.) The radius of a sphere is 3.5 cm. Find its surface area and volume.

(2.) The surface area of a sphere is 1018-2/7 sq.cm. What is its volume?

Solution: (3.) The length of equator of the globe is 44 cm. Find its surface area.

Solution: (4.) The diameter of a spherical ball is 21 cm. How much leather is required to prepare 5 such balls.

(5.) The ratio of radii of two spheres is 2 : 3. Find the ratio of their surface areas and volumes.

Solution:  (6.) Find the total surface area of a hemisphere of radius 10 cm. (use π = 3.14)

Solution:

Given,

Radius of hemisphere = 10a, π = 3.14

Total surface area of hemisphere = 3πr2

= 3 x 3.14 x 102

= 3 x 3.14 x 100

= 3 x 314

= 942 cm2

(7.) The diameter of a spherical balloon increases from 14 cm. to 28 cm. as air is being pumped into it. Find the ratio of surface areas of the balloons in the two cases.

Solution: (8.) A hemispherical bowl is made of brass, 0.25 cm. thickness. The inner radius of the bowl is 5 cm. Find the ratio of outer surface area to inner surface area.

Solition: (9.) The diameter of a lead ball is 2.1 cm. The density of the lead used is 11.34 g/c3 . What is the weight of the ball?

Solution:  (11.) How many litres of milk can a hemispherical bowl of diameter 10.5 cm. hold?

Solution: (12.) A hemispherical bowl has diameter 9 cm. The liquid is poured into cylindrical bottles of diameter 3 cm. and height 3 cm. If a full bowl of liquid is filled in the bottles, find how many bottles are required.

Solution:  Updated: October 2, 2021 — 4:29 pm

1. 2. 