ANSWERS: (1) diameter

(2) radius

(3) circumference

(4) d

(5) a

(6) b

(7) c

Make sure you understand these terms before going on.

THE GREEK LETTER

Just what does pi, or π, mean and where does it come from? You should understand

why you will use in solving areaofcircle problems.

π = 3.14

You already know from the definitions that π is the ratio of the circumference

to the diameter of a circle.

Ratio

Circumference__ = π = 3.14

Diameter

Look at the circle above. Take your pencil and measure off the length of the

diameter. Then, keeping the length of the diameter on your pencil, start at any

point on the circumference and imagine that you can wrap the pencil around the

circle. (You can see that this has been done on the circle above.) You should

discover that the length of the diameter will divide into the length of the

circumference a little more than three times. To be exact, 3.14 times. (This is a

little easier if done with a can and a piece of string.)