MCQ - 75-11927

Correct Answer: A

Explanation:

To find the answer, we need to first find the circumference of the circle then mulitply that by 4 because the racehorse is running 4 laps.

We know that the area of the circle is 36π. We can then find the radius.

${\displaystyle A=\mathrm{\pi <!--\; \pi \; -->}{r}^2}$

${\displaystyle 36\mathrm{\pi <!--\; \pi \; -->}=\mathrm{\pi <!--\; \pi \; -->}{r}^2}$

${\displaystyle r^2=36}$

${\displaystyle r=6}$

Because d = 2r, our diameter is 12.

We can now find the circumference.

C = dπ

C = 12π

Multiply the circumference by 4 (our racehorse is running 4 laps) to find the answer.

12π⋅4 = 48π