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A ball is dropped from a height of 30 feet. The ball bounces. After each bounce, the maximum height of the ball is 80% of the previous height. Write an nth term formula to model the situation and approximate the maximum height of the ball after 6 bounces.

User RobEarl
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1 Answer

6 votes
das is sum of geometric sequence
first is 30
imagine it
ball droppes 30 feet
bounces up 80% of that
then it has to bounce down again
then up
down
therfor, we summ up from 30 to 6thbounce, times 2 and minus 30 since the first bounce didn't start from ground (will include diagram)


so therefor
2(sum)-30 is the answer

the sum of a geometric sequence is

S_(n)= (a_(1)(1-r^(n)))/(1-r)
where Sn is the sum to the nth bounce
a1=first term
r=common ratio
n=which term
Sn=S6 (6th bonce)
a1=30
r=80% or 0.8

sub


S_(6)= (30(1-0.8^(6)))/(1-0.8)

S_(6)= 110.678

we then double then minus 30
2*110.678=221.357
minus 30
221.357-30=191.357 feet


you should use
dropped from x feet and max height is m percent of previous heigh, find total distance after n bounces (convert m% to decimal)
answer=
2[ (x(1-m^(n))/(1-m) ]-x





anyway, distance is 191.357 feet
User Tillebeck
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