Question

the circumference of a circle is c = 2(pie)r. determine the radius (r) for each circle with the given circumference. use 3.14 for pie (wont let me type the symbol in the instructions) and round to the nearest 10th of a unit if needed. include units in answer. 1. c = 62.8 in 2. c = 10 cm 3. c = 15.7 ft 4. c = 48 mm

Explanation:

Step1: Rearrange the formula for radius

Given \(C = 2\pi r\), we can solve for \(r\) by the formula \(r=\frac{C}{2\pi}\).

Step2: Substitute \(C = 62.8\) in and \(\pi=3.14\)

\(r=\frac{62.8}{2\times3.14}\)
\(r=\frac{62.8}{6.28}\)
\(r = 10\) in.

Step3: Substitute \(C = 10\) cm and \(\pi = 3.14\)

\(r=\frac{10}{2\times3.14}=\frac{10}{6.28}\approx1.6\) cm.

Step4: Substitute \(C = 15.7\) ft and \(\pi=3.14\)

\(r=\frac{15.7}{2\times3.14}=\frac{15.7}{6.28}=2.5\) ft.

Step5: Substitute \(C = 48\) mm and \(\pi = 3.14\)

\(r=\frac{48}{2\times3.14}=\frac{48}{6.28}\approx7.6\) mm.

Answer:

1. \(10\) in
2. \(1.6\) cm
3. \(2.5\) ft
4. \(7.6\) mm