Question

The ratio of the radius of two circles is 5 ∶ 4. What is the ratio of their areas?
1. 5 ∶ 4
2. 25 ∶ 16
3. 6 ∶ 7
4. 9 ∶ 13

Answer 1

Correct Answer - Option 2 : 25 ∶ 16

Given:

The ratio of the radius of two circles is 5 ∶ 4.

Formula Used:

Area of circle = πr²

Calculation:

Let the radius be 5x and 4x.

The ratio of area of circle = π (5x)²/π (4x)²

The ratio of area of circle = 25/16

∴ The ratio of area of circle is 25 ∶ 16.