when a ball is dropped, it bounces back up 4/5 of the height from the height it was dropped.If the ball dropped from a height of 200cm, how high does it go after bouncing twice.

1st bounce=0.2(4/5)=0.16m

2nd bounce=0.16(4/5)=0.128m or 128cm

To determine the height the ball reaches after bouncing twice, we need to calculate the heights of each bounce.

Let's break down the problem step by step:

1. First bounce: The ball is dropped from a height of 200cm, and it bounces back up to 4/5 of that height.
Height after the first bounce = (4/5) * 200cm = 160cm

2. Second bounce: The ball is dropped from the height attained after the first bounce, which is 160cm.
It bounces back up to 4/5 of that height.
Height after the second bounce = (4/5) * 160cm = 128cm

Therefore, after bouncing twice, the ball reaches a height of 128cm.

To solve similar problems, you can follow these steps:
1. Determine the height of the first bounce by multiplying the bounce factor (4/5) by the initial height.
2. Use the height after each bounce as the new starting height for the subsequent bounce(s) until you reach the desired number of bounces.