Question

1. The Volume Of A Sphere Is 2100 cm Cube And Its Radius Is xcm. Find The Value Of x And Hence The Curved Surface Area Of The Sphere(take pie=22/7). 2. A Hemispherical Bolw Of Diameter 30cm Has The Same Volume As A Cylinder Of Height 22.5cm. Find The Radius Of The Cylinder(take pie=22/7).

Answer 1

4π/3 x^3 = 2100
x^3 = 1575/π
a = 4πx^2 = ?

2π/3 r^3 = 2π/3*15^3 = 2250π
for the cylinder, then
πr^2 45/2 = 2250π
r = 10

Answer 2

Vary good to me