If pipe B fills a container at a constant rate in 100 minutes, how many minutes does it take pipe A, working...

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Economist GMAT

If pipe B fills a container at a constant rate in 100 minutes, how many minutes does it take pipe A, working at is own constant rate, to fill the same container?

1) Pipe A and pipe B together fill the container at (1/4) the time it takes pipe A alone.
2) Pipe A and pipe B together fill the container at (3/4) the time it takes pipe B alone.

OA D

[Chan96]

Lets try with a framework /Easy approach
we know the rate and time for one pipe
so sum it up in r*t=w like one is full of variable that is pipe a 1/t *t =1 and other is pipe b value 1/100*100=1
1. gives a relation . we have only one t we can find the solution so Statement 1 is sufficient
2. gives a relation we have only one t we can find the solution so Statement 2 is sufficient

OA : D
Be cautious if we have a quadratic but that wouldn't happen in rate time question most probably