Question 1185115
<pre>
It goes up 20 feet and then comes back down 20 feet. That's 40 feet for the
first term. Then it goes up 16 feet and comes back down 16 feet. So that's 32
feet for the second term.  We have an infinite geometric series with
a<sub>1</sub> = 40 and r = 80% = 0.8

40+32+25.6+...

{{{S[infinity]}}}{{{""=""}}}{{{a[1]/(1-r[""])}}}{{{""=""}}}{{{40/(1-0.80)}}}{{{""=""}}}{{{200}}} feet.

Edwin</pre>