Here is the question:

a ball is dropped from a height of 3m and bounces on the ground . At the top of each bounce, the ball eaches 60% of its previous height. Calculate the total distance travelled by the ball when it hits the ground for the fifth time?

I know you need the n, r and a values.
I got r=0.6 n=5 and a=3 but every where i look they have a=6 and subtract 3 off the final answer? why?

1 answer

because there was no bounce at first - just a drop.

When it hits the ground for the 5th time, it has made a single 3-foot drop, and then 4 round-trip bounces.