find the circumference of a circle that has a diameter of three inches. give exact value

circumference=pi*diameter

C=(pi)(d)

=3.14159*3

=9.42477 in

this is not an exact value because pi is an irrational number, a non-ending, non-repeating decimal,

in other words, it cannot be written as a simple fraction a/b

## Comments

exactmay have different meanings for different people. Maybe to the student exact meant 3 times some approximate value of pi. Or maybe 3pi is what the student was looking for. Anyway, we gave him both answers to choose from.