Question 1194691
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A rectangular trough is 10 ft. long and 3 ft wide. 
Find how fast the surface {{{highlight(rises)}}}, if water flows in 
at the rate of 12 cu.ft. per min.
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<pre>
To find the rate of increasing water level in the trough,

divide the inflow rate of 12 cu.ft by the area of the through 10*3 = 30 sq.ft.


You will get the answer
    
    the rate of increasing water level in the trough = {{{12/30}}} = {{{4/10}}} ft/minute = 0.4 ft/minute.
</pre>

Solved and explained.