Question

Seth wants to create a replica of a doughnut for a rooftop sign for his bakery. The replica has a diameter of 18 feet. The diameter of the hole in the center is equal to the radius of the replica.

A. Write a numerical expression for the length of the string of lights needed.
B. Simplify your expression. (Hint: Treat π like a variable.)
C. Find the length of the string. Use 3.14 as an approximation for π. Round your answer to 2 decimal places and use the correct unit of measure.
D. Explain how you found the answer. Include your thoughts and the steps you took to figure it out.

Answer 1

sC = 2Πrd = 18d = 2rr = 9C = 2Π9C = (2)(3.14)(9)C = 56.52 feetThis is the length of the string of lights.

Explanation: