Question

5. If a circle has an area of 706.5 cm what is its circumference?

94.2 cm
329.6 cm
140.5 cm
398.1 cm

Answer 1

Answer: 94.2 cm

Explanation:

First, we know the formula to solve for the radius if given the area. It is a transformed version of the equation to solve for the area (A = πr²). We will substitute our area (A) and solve by dividing and finding the square root.

`\displaystyle r = \sqrt{(A)/(\pi) }`

`\displaystyle r = \sqrt{(706.5\; cm)/(\pi) }`

r = 15

Next, we will solve for the circumference using this radius and the given formula.

C = 2πr

C = 2π(15)

C ≈ 94.24778 ≈ 94.2 cm