A beer manufacturer needs to convert a tank containing 40 gallons of regular beer into light beer by adding water. Initially, water is pumped into the tank at the rate of 4 gal/min. And the perfectly mixed solution is allowed to flow out of the tank at the rate of 2 gal/min. The light beer has 1/3 calories of regular beer. That is, it is 2/3 water. How long will it take to convert the regular been into light beer?(adsbygoogle = window.adsbygoogle || []).push({});

Can someone please help me set up and solve this problem. Im confused on what to use as the concentration of the solution.

Formula: da/dt=R1-R2

R1=(rate of substance entering)(concentration)

R2=(rate of substacne leaving)(concentration)

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# Homework Help: Differential Equation (mixture problem)

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