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The curved surface area of a cylinder is half of its total surface area. If its height is 102 cm, then find its radius (in cm).
Question

The curved surface area of a cylinder is half of its total surface area. If its height is 102 cm, then find its radius (in cm).

A.

103

B.

108

C.

100

D.

102

Correct option is D

Given:

- The curved surface area (CSA) is half of the total surface area (TSA).
- The height of the cylinder is 102 cm.
- We need to find the radius of the cylinder.
Formula Used:
Curved Surface Area (CSA) of a cylinder = 2πrh
Total Surface Area (TSA) of a cylinder = 2πr(r + h) 

Solution:
: Relationship between CSA and TSA
According to the given condition:
CSA = (1/2) × TSA
2πrh = (1/2) × 2πr(r + h)
h = (1/2) × (r + h)
2h = r + h
r = 2h - h = h
We are given that the height h = 102 cm, so:
r = 102 cm
The radius of the cylinder is 102 cm. 

The curved surface area of a cylinder is half of its total surface area. If its height is 102 cm, then find its radius (in cm).

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