Question

The total surface area of solid hemisphere is 462 cm2. If the curved surface area of it is 308 cm2 , then the area of the base of the hemisphere is (A) 308 cm2 (B) 231 cm2 (C) 154 cm (D) 1078 cm2​

Answer 1

Step-by-step explanation:

Correct option is

A

7

Let r be radius of solid hemisphere.

Total surface area of solid hemisphere =3πr

2

It is given that total surface area is 462 cm

2

⇒3πr

2

=462

⇒πr

2

=154

⇒r

2

=154×

22

7

⇒r

2

=49

⇒r=7 cm