# math

a ping pall ball is dropped from 20m on a horizontal roof of a house and always reduce to 1/8of previous fall in each bounce .what height does it fall in 7th time

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1. If you mean that its bounce is 1/8 less each time, then 20 * (7/8)^7
If you mean that each bounce is 1/8 as high as the previous bounce, then 20 * (1/8)^7

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