SOLUTION: Liquid is flowing into a tank. Pump can pump from tank faster than this flow. Pump starts when tank is full. How long will pump run to empty contents of tank plus all liquid enteri

Question 807367: Liquid is flowing into a tank. Pump can pump from tank faster than this flow. Pump starts when tank is full. How long will pump run to empty contents of tank plus all liquid entering tank during this time?
Answer by josgarithmetic(39620) (Show Source): You can put this solution on YOUR website!
Concept is R*t=v;
R is fill or empty rate in vessel per time, whatever units are needed.
r is time, in whatever unit needed.
v is vessel or the tank as a unit itself, in whatever volume unit if necessary, but the focus may be on "vessel" as a unit.

Your example's rate for filling is F. The rate for emptying is E for Empty or Evacuate. and . The actual rate occurring will be for emptying the tank. This rate is F+E tanks per time. This rate will be negative because E|F|.

Your example starts with v=1, but you can call this a reference point of zero if you find it simpler.

Solving for t for this emptying to be done gives .
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