Question

The circle formed by the blades of a fan has a circumference of eighty-one and five-sevenths inches. What is its diameter? Use twenty-two sevenths for pi.

A. twelve inches

B. eighteen inches

C.twenty-one inches

D.twenty-six inches

Answer 1

Using the formula for circumference:
\[Circumference = \pi \times Diameter\]
You know that the circumference is 81 5/7, and pi is 22/7, so:
\[81\frac{ 5 }{ 7 } = \frac{ 22 }{ 7 }d\]\[\frac{ 22 }{ 7 }d = \frac{ 572 }{ 7 }\]
You can rearrange that equation to find d.

Answer 2

SO D

Answer 3

Yep.