Question

The cylinder is 20cm high and radius of its circular face is 3cm What is the total perimeter and area of the whole net?

Answer 1

Answer: $52\ cm,\ 176.55\ cm^2$

Step-by-step explanation:

Given

The cylinder is 20 cm high

The radius of the cylinder is $r=3\ cm$

The total area of the figure is the sum of the rectangle and two circles

$\Rightarrow \text{Perimeter P=}2[h+2r]\\\Rightarrow P=2[20+6]\\\Rightarrow P=52\ cm$

The total area of the figure is

$\Rightarrow \text{Area A=}h\times 2r+2\pi r^2\\\Rightarrow A=20\times 6+2\times \pi \times 3^2\\\Rightarrow A=120+18\pi\\\Rightarrow A=176.55\ cm^2$