Question

1) Find the radius of a sphere whose surface area is 154 cm?​

Answer 1

3.5 cm

Solution,

Let x be radius

Given,

=>Surface area=154cm²

∴4πx²=154

x²=154×7 =49

4×22 4

x=√49/4x=3.5 cm

Answer 2

Answer:

3.5

Step-by-step explanation:

Aussme π = 22/7 Unless stated otherwise

Let r be the radius of the sphere

surface area =4πr²

154cm2=4πr²

154cm²=4×22/7×r²

154×7/22×4cm²=r²

r²=12.25

r=√12.25

r=3.5

thus the radius of the sphere is 3.5cm