Question

A circular plate has circumference 20.7 inches. What is the area of this​ plate? Use 3.14 for

Answer 1

C=2pir
20.7=2*3.14*r
20.7=6.28r
20.7/6.28=6.28r/6.28
r=3.3
A=pir^2
A=3.14*3.3^2
A=34.1 in^2

Answer 2

A ≈ 34.1 in²

Explanation:

Using the formulas of area & circumference:

A = πr2

C = 2πr

Solving for A:

A = C2

4·π = 20.72

4·π = 34.09815 in²

4·π ≈ 34.1 in²