Calculate Circle Radius Given Circumference C=81: Geometric Problem

Question

Calculate the radius based on the circumference given in the figure:

00:00 Find the circle's radius (R)

00:03 We'll use the formula for calculating circle circumference

00:11 We'll substitute appropriate values according to the given data and calculate to find the radius

00:23 We'll isolate radius R

00:35 We'll substitute the value of pi and calculate to find radius R

00:48 And this is the solution to the problem

12.891