Question

find the radius (r) of a tree trunk with a circumference of 157 inches. c = 157 in. r = in. r = c ÷ π ÷ 2 use 3.14 for π

Explanation:

Step1: Recall the formula for radius from circumference

The formula given is \( r=\frac{C\div\pi}{2} \), which can also be written as \( r = \frac{C}{2\pi} \). We know \( C = 157 \) inches and \( \pi\approx3.14 \).

Step2: Substitute the values into the formula

First, calculate \( 2\pi \): \( 2\times3.14 = 6.28 \). Then, divide the circumference by \( 2\pi \): \( r=\frac{157}{6.28} \).

Step3: Perform the division

\( 157\div6.28 = 25 \).

Answer:

25