The speed of a baseball pitcher's fastball is 84.2 miles per hour. His fastball is 10%
faster than his curveball, and his curveball is 5% faster than his change-up. What is
the speed of the pitcher's change-up, in miles per hour, to the nearest tenth?
A . 69.2
B . 72.9
C . 73.2
D. 76.5