Answer :
0.375. I Made a list so each time I dropped it, I divided the original number in half
1: 6inch
2: 3inch
3: 1.5inch
4: 0.75Inch
5: 0.375inch
1: 6inch
2: 3inch
3: 1.5inch
4: 0.75Inch
5: 0.375inch
so, the answer is 17.25
the ball DOES fall 5 times, but it only re-bounces 4 times.