Question

If the total surface area a solid right circular cylinder is $200\pi {cm}^2$ and its radius is $5cm$, then the sum of its height and radius is

• A. $20cm$
• B. $25cm$
• C. $30cm$
• D. $15cm$

Answer 1

The correct option is A $20cm$

We have,

Total surface area of cylinder $=200\pi c{m}^2$

$r=5cm$

We know that total surface area of cylinder

$=2\pi r(r+h)$

So,

$2\pi \times 5(5+h)=200\pi$

$5(5+h)=100$

$5+h=20$

$h=15cm$

So, the sum of the $r$ and $h$

$r+h=5+15=20cm$

Hence, this is the answer.