# The distance around a basketball, or circumference, is about three times the circumference of a softball. Using a variable, what is the expression that represent the circumference of a basketball?

##### 1 Answer
Jul 19, 2018

${C}_{b a s k e t b a l l} = 6 \pi {r}_{s o f t b a l l}$

or $\text{ } {C}_{b a s k e t b a l l} = 3 \pi {d}_{s o f t b a l l}$

#### Explanation:

Given: The circumference of a basketball is 3 times the circumference of a baseball.

In terms of the radius:

${C}_{s o f t b a l l} = 2 \pi {r}_{s o f t b a l l}$

${C}_{b a s k e t b a l l} = 3 \left(2 \pi {r}_{s o f t b a l l}\right) = 6 \pi {r}_{s o f t b a l l}$

In terms of the diameter:

${C}_{s o f t b a l l} = \pi {d}_{s o f t b a l l}$

${C}_{b a s k e t b a l l} = 3 \left(\pi {d}_{s o f t b a l l}\right) = 3 \pi {d}_{s o f t b a l l}$