Question

The ratio of the height and radius of a right circular cylinder is 7 : 5 and its volume is 550 cm³. Its radius is ______.

Options

• 10 cm

• 3 cm

• 4 cm

• 5 cm

Answer 1

The ratio of the height and radius of a right circular cylinder is 7 : 5 and its volume is 550 cm³. Its radius is 5 cm.

Explanation:

Let the height be 7x, and the radius be 5x. Substituting these values into the volume

V = πr²h, we get 550 = `22/7 × 25x^2 × 7x,`

which simplifies to 550 = 550x³

Solving this gives x = 1, so the radius is 5(1) = 5cm.