SOLUTION: We are standing on a roof and we throw a ball from a certain height.The height of the bounce of the ball is equal to 70% of the height from where we threw it. Also each successive

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: We are standing on a roof and we throw a ball from a certain height.The height of the bounce of the ball is equal to 70% of the height from where we threw it. Also each successive      Log On


   



Question 185195: We are standing on a roof and we throw a ball from a certain height.The height of the bounce of the ball is equal to 70% of the height from where we threw it.
Also each successive bounce is 70% of the height it last bounced to.
If the height of the third bounce is 10.29m., at what height are we standing>????????????????????????????????? PLZZZZZZZZZZZZZZZ HELPPPPPPPPPPP !!!!!!!!!!!!! I ReALLY NEED HELPPPPPPPPPPPPPPPPPP !!!!!!!!!!

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Suppose the roof is X meters high.

Therefore the first bounce was 70% of X or .7X meters

Therefore the second bounce was 70% of .7X or .7(.7X) or .49X meters

Therefore the third bounce was 70% of .49X or .7(.49X) or .343X meters

So we set .343X meters = to 10.29 meters:


        .343X+=+10.29
        ++++X+=+10.29%2F.343
        ++++X+=+30meters

Edwin