Question

The graphite in a pencil has a diameter of 1.5 millimeters and is surrounded by wood that is 2 millimeters thick. what is the distance around the pencil? use 3.14 for ππ. round to the nearest millimeter.

Answer 1

17mm is the answer.

To solve this:

1.) Find the radius of the entire pencil.

The radius of the graphite is .75 (half the diameter) and the thickness of the wood is 2, so 2 plus .75 gives you a total radius of 2.75.

2.) Using this radius, find the circumference of the entire pencil using the equation C = 2 • pi • r.

C = 2 • pi • r
C = 2 • 3.14 • 2.75
C = 17.27 (17 is the answer after rounding to the nearest millimeter)