Question

if the total surface of solid sphere is 98.56cm2,then find the radius of the sphere.
plzzzzzzzzzzzzzz do as fast as possible
explain
it?

Answer 1

Formula used: Total surface area of a sphere = 4π r²

Given, area 4π r² = 98.56 cm²                   {let π = 22/7}
           4 × 22/7 × r² = 98.56
                            r² = 98.56 × 7/22 × 1/4
                            r² = 689.92
                            r = √689.92
                            r = 2.8 cm

Therefore, Radius of the sphere = 2.8 cm

Answer 2

Hi,

Let the radius of the

solid Sphere = r cm

Total Surface Area of the

Sphere = T.S.A = 4πr² ----( 1 )

According to the problem given,

T.S.A = 98.56cm² ---( 2 )

( 1 ) = ( 2 )

4πr² = 98.56

4×(22/7)×r² = 9856/100

r² = ( 9856 × 7 )/( 100 × 4 × 22 )

r² = ( 112 × 7 )/100

r = √ [ ( 4 × 4 ) × ( 7 × 7 ) ] / √( 10 × 10 )

r = ( 4 × 7) / 10

r = 28 / 10

r = 2.8 cm

Therefore,

Radius of the solid Sphere (r) = 2.8cm

I hope this helps you.

:)