<PRE><B>Question 592336</B>
A drain can empty 3/4 of a sink in 1 minute and the faucet can fill 5/6 of the sink in 1 minute. If the faucet is on and the drain is open, how long will it be before the sink overflows?

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let x=minutes sink overflows
5x/6-3x/4=1
LCD:12
10x-9x=12
x=12
ans:
The sink will overflow in 12 minutes</PRE>