Hi All,

We're given the rates of two entities that will share a job together - this is the standard "set-up" for a Work Formula question.

Work Formula = (A)(B)/(A+B) where A and B are the respective amounts of time needed to individually complete a job.

Pump A = 2 hours to fill a tank

Pump B = 1/2 hour to fill a tank

Working together, it takes....

(2)(1/2)/(2 + 1/2) = 1/2.5 hours to fill the tank together...

1/2.5 = 2/5 hours

Final Answer:

GMAT assassins aren't born, they're made,

Rich

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Rich Cohen

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