Question

the browns are putting a rock border around the circumference of their circular swimming pool. if the pool has a 10 - foot radius, how many feet of rock do they need?

Explanation:

Step1: Recall the formula for the circumference of a circle

The formula for the circumference \( C \) of a circle is \( C = 2\pi r \), where \( r \) is the radius of the circle.

Step2: Substitute the given radius into the formula

We are given that the radius \( r = 10 \) feet. Substituting this value into the formula, we get \( C = 2\pi(10) \).

Step3: Simplify the expression

Simplifying \( 2\pi(10) \), we have \( C = 20\pi \). If we use the approximation \( \pi \approx 3.14 \), then \( C \approx 20\times3.14 = 62.8 \) feet.

Answer:

They need approximately \( 62.8 \) feet of rock (or \( 20\pi \) feet if we leave it in terms of \( \pi \)).