Let m > 0 be a constant. Suppose a tank starts with 10kg of salt water...

Let m > 0 be a constant. Suppose a tank starts with 10kg of salt water with 1% salt by mass. Suppose further that every hour, m kg of salt water with a concentration of 10% salt is added, and 2kg of the water in the tank is drained. The solution is kept well mixed at all times.

(a) (2 points) Write a diﬀerential equation that describes the amount of salt in the water.

(b) (5 points) How long does it take for the water to reach 5% concentration if m = 3.
(c) (5 points) Give a (simpliﬁed) equation describing a value for m such that the solution to reaches exactly 5% concentration in exactly 1 hour.

Expert Solution

milcah answered 2 years ago

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