Question

If the radius and the height of a cylinder are 2 cm and 3 cm respectively, then its total surface area is:

• A. $20\pi {\text{cm}}^2$
• B. $16\pi {\text{cm}}^2$
• C. $12\pi {\text{cm}}^2$
• D. $6\pi {\text{cm}}^2$

Answer 1

The correct option is A $20\pi {\text{cm}}^2$

Given, the radius of the cylinder$\left(r\right)=2\text{cm}$
and the height of the cylinder$\left(h\right)=3\text{cm}$

The total surface area of the cylinder $=2\pi r^2+2\pi rh$
$=2\pi (2{)}^2+2\pi \times 2\times 3$
$=(2\pi \times 4)+(2\pi \times 6)$
$=8\pi +12\pi$
$=20\pi {\text{cm}}^2$
Hence, option (a.) is the correct choice.