Question

Total surface area of a right circular cylinder is 440 cm${}^2$. If the radius of the right circular cylinder is 7 cm, find the height of the right circular cylinder.

• A. 5 cm
• B. 3 cm
• C. 2 cm
• D. 7 cm

Answer 1

The correct option is B 3 cm

Given: Radius = 7 cm, total surface area = 440 cm${}^2$

Total surface area of the cylinder = $2\pi r(h+r)$

440 = $2\times \frac{22}{7}\times 7(h+7)$
h + 7 = 10
h = 10 - 7 = 3 cm