Question

Answer in detail
If possible in a picture


Question 6

Answer 1

Given:
h = 7 cm
TSA = 2πr(r+h) = 4620 cm²
Area of the ring at the bottom = 115.5 cm²

Curved surface area(CSA) = TSA - Base
and Top Areas

= 4620 - 2(115.5) = 4620 - 231 = 4389 cm²

CSA = 2πrh = 438.9
2 × 3.14 × r × 7 = 438.9

r= 4389/43.96 = 9.98 cm

Base area of the cylinder = πr²
= 3.14 × 9.98 × 9.98
= 312.99 cm²

Area of base of the hollow cylinder space = 312.99 - 115.5 = 197.4 cm²

To find radius of base of the hollow cylinder,

Area = π R²
197.4 = 3.14 R²
R² = 62.86
R = 7.92 cm

Therefore,
Thickness = Radius of cylinder - Radius of hollow cylinder

= 9.98 - 7.92
Thickness of the ring = 2.06 cm.

- WonderGirl