A water tank can be emptied by using one pump for 5 hours.
Chapter 2, Problem 34(choose chapter or problem)
A water tank can be emptied by using one pump for 5 hours. A second, smaller pump can empty the tank in 8 hours. If the larger pump is started at 1:00 P.M., at what time should the smaller pump be started so that the tank will be emptied at 5:00 P.M.?
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