Suppose you drop a tennis ball from a height of 15 feet. After the ball hits the floor, it rebounds to 85% of its previous height. How high will the ball rebound after its third bounce? Round to the nearest tenth.

Question

littlebird · Answer

Bounce One .85(15)
Bounce Two .85(.85(15))
Bounce Three .85(.85(.85(15))

anonymous · Answer

Could you please explain why you did it this way if that's ok?

anonymous · Answer

@Littlebird 
the problem you were helping @allay with look at it again

littlebird · Answer

The ball starts at a height of 15 feet
The question tells you that after the ball bounces, it goes up to 85% of its previous height.
The first bounce would be 85% of 15
The second bounce would be 85% of 85% of 15

anonymous · Answer

Would you happen to know what I did wrong doing this problem before you helped me please? 
$$a_{1}=15 $$ $$a_{n}=0.85$$
$$a_{_{3}}=0.85(15)=12.75$$
0.85(12.75)=10.8375

@Littlebird

littlebird · Answer

In order to solve this problem, one must understand that 15 was the height of the ball BEFORE it bounced 

a3 tells you the height of the ball after the first bounce

anonymous · Answer

thankyou!