One ball will drop from a certain height. The height it will

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One ball will drop from a certain height. The height it will reach after rebounding from the floor is 60 percent of the previous height. The total travel is 292cm when it touches the floor on third time. What is the value of the original height?
A. 80cm
B. 90cm
C. 100cm
D. 120cm
E. 130cm

*An answer will be posted in 2 days.

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by regor60 » Wed Jun 22, 2016 4:08 am
Max@Math Revolution wrote:One ball will drop from a certain height. The height it will reach after rebounding from the floor is 60 percent of the previous height. The total travel is 292cm when it touches the floor on third time. What is the value of the original height?
A. 80cm
B. 90cm
C. 100cm
D. 120cm
E. 130cm

*An answer will be posted in 2 days.

C

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by Max@Math Revolution » Sun Jun 26, 2016 6:26 am
If we consider the initial height as x, then from x+2(60%)x+2(60%)^2(x)=292, we get x=100. Hence, the correct answer is C.