document.write( "Question 944000: Officials begin to release water from a full man-made lake at a rate that would empty the lake in 20 weeks, but a river that can fill the lake in 30 weeks is replenishing the lake at the same time. how long does it take to empty the lake? \n" ); document.write( "
Algebra.Com's Answer #575573 by josgarithmetic(39620)\"\" \"About 
You can put this solution on YOUR website!
Sum of the rates! The unit is LAKE per WEEKS.\r
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\n" ); document.write( "\n" ); document.write( "\"1%2F20-1%2F30\"
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