pi ( Rbig^2 - Rsmall^2)
= 3.14159 ( 625 - 400)
=
Bollough Junior High is planning to build a new circular fountain in the courtyard. One contractor has suggested building a fountain that has a diameter of 40 feet. Another contractor has suggested building a fountain that has a diameter of 50 feet. How many square feet greater is the area of the second fountain than the area of the first fountain?
2 answers
since the radii are 20 and 25 ft, you want
π(25^2 - 20^2) = 225π ft^2
π(25^2 - 20^2) = 225π ft^2