The base of a lampshade is in the shape of a circle and has a diameter of 13 inches. What is the circumference, to the nearest tenth of an inch, of the base of the lampshade? (Use 3.14 for π.)
The formula for the circumference of a circle is C=2πr, or πd where r is the radius. Substitute the values! C=πd C=(3.14)(13 in) C=40.82 in Since the given is round it off to the nearest tenth, then the answer is: C=40.8 in
