posted by Marisol .
A ball has a 75% rebound ratio. When you drop it from a height of 16 ft, it bounces and bounces...
When it strikes the ground for the second time, the ball has traveled a total of 28 ft in a downward direction. How far downward has the ball traveled when it strikes the ground for the 17th time?
It is a geometric progression (GP) with a ratio of 3/4.
The sum to n terms of a GP is:
Substitute n=17 in the above formula to get S(17), the total downward distance.