The diameter of a circle is 8 miles. What is the circle's area?

Solution:

The diameter of a circle is the longest chord in the circle that passes through the center of the circle. Generally the diameter of the circle will be twice the radius of the circle or radius is half of the diameter i.e., if ‘d’ is diameter and ‘r’ is radius of the circle, d = r/2.

Given that, the diameter of a circle is 8 miles

⇒ Radius = r = d/2 = 8/2 = 4 miles

∴ Area of the circle is = πr² = (π)(4²) = 16π miles square.

Example: Find the area of the circle whose radius is 7cm. Use π = 22/7

Given that, radius of a circle is 7cm

Area of the circle is = πr² = (π)(7²) = 49π= 49(22/7) = 154 cm²

The diameter of a circle is 8 miles. What is the circle's area?

Summary:

If the diameter of a circle is 8 miles, then the circle's area is 16π miles square.