Help!! I'll Fan and Medal ;v;

Question

anonymous · Answer

What is the total distance of the height each ball has traveled in the first five heights? Use the geometric series formula, Sn = the quantity of a sub 1 minus a sub 1 times r to the n power, all over 1 minus r  and show your work.

anonymous · Answer

attachment

anonymous · Answer

@ganeshie8 I'm so sorry to bother you once again!!

anonymous · Answer

If it helps, this is what I have so far! 
s5= 3-(3) (0.85)/ (1-0.8)
s5 = 3-(3)(.328)/(1-0.8)
s5 = 3-0.98/.92

ganeshie8 · Answer

look at the Ball1 column
whats the common ratio ?

anonymous · Answer

The common ratio for ball 1 is 0.3 @ganeshie8

anonymous · Answer

wait no 0.8 sorry

anonymous · Answer

Ball 1: 0.8
Ball 2: 0.63
Ball 3: 0.3

ganeshie8 · Answer

That looks good!

ganeshie8 · Answer

and notice they all have the same first term : $a_1 = 3$

ganeshie8 · Answer

also number of terms is same for all of them : $n = 5$

anonymous · Answer

I see!! Thank you ;v; But where do I go on from where I left off? @ganeshie8

ganeshie8 · Answer

just plug the numbers into the formula

ganeshie8 · Answer

$$S = \dfrac{a_1 - a_1r^n}{1-r}$$

ganeshie8 · Answer

for Ball1 : 
$$S = \dfrac{3 - 3 (0.8)^5}{1-0.8}$$

use ur calculator to evaluate that

ganeshie8 · Answer

http://www.wolframalpha.com/input/?i=+%5Cdfrac%7B3+-+3+%280.8%29%5E5%7D%7B1-0.8%7D

anonymous · Answer

Oh!! Okay I get it now !! Thank you so much @ganeshie8

anonymous · Answer

so the awnser would be 10.08 correct?

ganeshie8 · Answer

thats right for Ball1 !