Question

use the formula $c = \pi d$ to find the circumference of each circle below. round off decimal answers to a single decimal place.

1. $c = \underline{\quad\quad\quad}$
2. $c = \underline{\quad\quad\quad}$
3. $c = \underline{\quad\quad\quad}$

Explanation:

Step1: For the first circle (28 in diameter)

The formula for circumference is \( C = \pi d \). Here, \( d = 28 \) in. So, \( C=\pi\times28\approx3.1416\times28 = 87.9648 \). Rounding to one decimal place gives \( 88.0 \) in.

Step2: For the second circle (51 ft diameter)

Using \( C = \pi d \), with \( d = 51 \) ft. \( C=\pi\times51\approx3.1416\times51 = 160.2216 \). Rounding to one decimal place gives \( 160.2 \) ft.

Step3: For the third circle (56 m diameter)

Using \( C = \pi d \), with \( d = 56 \) m. \( C=\pi\times56\approx3.1416\times56 = 175.9296 \). Rounding to one decimal place gives \( 175.9 \) m.

Answer:

1. \( C = 88.0 \) in
2. \( C = 160.2 \) ft
3. \( C = 175.9 \) m