Question

If a sphere is cut into two hemispheres whose total surface area is
90 cm^2, then what is the surface area of sphere?​

Answer 1

Answer:

step-by-step explanation:

Let :radius of sphere=r

total surface area of hemisphere=3×22/7×r²

90 =3×22/7×r²

90 ×4 =4×3×22/7×r² ....(m.b.s.by 4)

4×22/7×r² =360/3

4×22/7×r² =120cm²

Answer 2

Answer:

Let :radius of sphere=r

total surface area of hemisphere=3×22/7×r²

90 =3×22/7×r²

90 ×4 =4×3×22/7×r² ....(m.b.s.by 4)

4×22/7×r² =360/3

4×22/7×r² =120cm²