Question

Find the ratio between TSA of a cylinder to CSA given that its height and radius are $7.5$ and $3.5$ cm.

Answer 1

Given radius of the cylinder$\left(r\right)=3.5$ $cm$

height of the cylinder$\left(h\right)=7.5$ $cm$

curved surface area(CSA)$=2\pi rh=2\pi \times 3.5\times 7.5=52.5\pi cm$

total surface area(TSA)$=2\pi rh+2\pi r^2=2\pi \times 3.5\times 7.5+2\pi \times {3.5}^2=52.5\pi +24.5\pi =77\pi cm$

Ratio$=\frac{TSA}{CSA}=\frac{77\pi }{52.5\pi }=1.47$