<PRE><B>Question 828690</B>
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hose rate:
r = v/t = 1/4
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drain rate:
r = v/t = 1/7
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net rate:
1/4 - 1/7
7/28 - 4/28
3/28
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time = 1/rate
net time to fill the tub with hose and drain open = 28/3 = 9.333333 = 9 hours and 20 minutes
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Solve systems of linear equations up to 6-equations 6-variables:
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