Question

A solid cylinder with a height of 8 units and a radius of 3.5 units is to be covered with a paper sheet. If the cost of the paper sheet is ₹40 per 5 square units, the cost (in ₹) of covering the cylinder is________.(Take ∏=22/7)

• A. 2268
• B. 1664
• C. 2024
• D. 1012

Answer 1

Answer:

C. 2024

Given:

• Radius (r = 3.5) units

• Height (h = 8) units

• Cost of paper = ₹40 per 5 sq units

• (\pi = \frac{22}{7})

Since it is a solid cylinder, it must be covered completely ⇒ use Total Surface Area (TSA).

$\text{TSA} = 2\pi r(h + r)$
$\text{TSA} = 2 \times \frac{22}{7} \times 3.5 \times (8 + 3.5)$

Simplify:

$(2 \times \frac{22}{7} \times 3.5 = 22)$

$\text{TSA} = 22 \times 11.5 = 253 \text{ sq units}$

Total cost

$\text{Cost} = 253 \times 8$= ₹2024