Answer: Circumference: C = 2πr = 16.3
2(3.14)r = 16.3
r = 16.3/6.28
r = 2.5955414
Area: A = πr2
A = 3.14(2.5955414)2
A = 21.15366242 in2
Rounded to nearest whole number the area is 21 in2
Explanation:
* Lets revise some rules of a circle
- The circumference of a circle = 2πr , where r is the radius of it
- The area of the circle = πr²
* Lets solve the problem
∵ A circular plate has circumference 16.3 inches
∵ The circumference = 2πr
∵ π = 3.14
- Lets find the radius of the plate
∵ 16.3 = 2(3.14)r
∴ 16.3 = 6.28r
- Divide both sides by 6.28
∴ r = 16.3/6.28 = 2.5955 ≅ 2.6
∴ The radius of the plate is 2.6 inches
* Lets find the area of the plate
∵ The area = πr²
∵ π = 3.14
∵ 4 = 2.6
∴ The area = 3.14(2.6)² = 21.22 ≅ 21
* The area of the plate is 21 inches