Question 1108048
Pump 1
18 hours to fill 1 tank


Pump 1 plus Pump 2
6 hours to fill {{{3/5}}} tank


Pump 2
x unknown hours to fill 1 tank


{{{1/18+1/x=(3/5)/6}}}------solve to find the time for just pump #2 to fill 1 tank-ful by itself.


{{{1/18+1/x=1/10}}},  LCD is 180x,...

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{{{x=22&1/2}}}-------hours for pump #2 to fill 1 tank.



The question means, how much time for pump #2, to fill {{{2/5}}} of the tank.