# The Surface Area of a Sphere is the Same as the Curved Surface Area of a Cone Having the Radius of the Base as 120 Cm and Height 160 Cm. Find the Radius of the Sphere. - Mathematics

The surface area of a sphere is the same as the curved surface area of a cone having the radius of the base as 120 cm and height 160 cm. Find the radius of the sphere.

#### Solution

Lateral height of cone

l = sqrt((120)^2 +(160)^2)

= sqrt(14400 + 25600)

= sqrt 40000

= sqrt 200

Surface area of sphere = surface area of cone

$4 \pi r_1^2 = \pi r l$

${r_1}^2 = \frac{rl}{4}$

${r_1}^2 = \frac{120 \times 200}{4}$

${r_1}^2 = 6000$

r_1 = sqrt6000

= 77.46 cm

Is there an error in this question or solution?

#### APPEARS IN

RD Sharma Class 10 Maths
Chapter 14 Surface Areas and Volumes
Q 32 | Page 82