A circular fire pit needs a metal edging strip all the way around. The circle has a radius of 50 inches. Using 3.14 for pi, how long a strip should be bought?

1. The distance around a circle is its circumference, given by C equals 2 times pi times r. 2. Substitute 3.14 for pi and 50 inches for r: C is approximately 2 times 3.14 times 50. 3. Multiply: 2 times 3.14 is 6.28, and 6.28 times 50 equals 314. 4. The strip should be about 314 inches long. 5. 157 inches uses pi times r and forgets the factor of 2, so the strip would only reach halfway around. _Source: OpenStax Prealgebra (CC BY 4.0), Ch 5 "Decimals", section 5.3 Decimals and Fractions_