5. shara's new lawn sprinkler watered a circular area with three times the radius of the old sprinkler. how many times greater was the area watered by the new sprinkler than the area watered by the old sprinkler?

a)3
b)6
c)9
d)36

The answer is C. when you have questions like these, its best to plug in an easy number and test it out. 

Say the original radius was 2. That means the area of that sprinkler was 12.56 (if you use the formula Pi(radius)squared. 

a number 3 times bigger then 2, is 6. (2 times 3 = 6) There fore, following the same formula as before, you plug that number in and get 113.04 as the area of the new sprinkler. 

113.04 divided by 12.56 is 9