A 50-gallon barrel is filled completely with pure water. Salt water with a concentration of 0.3 pounds/gallon is then pumped into the barrel, and the resulting mixture overflows at the same rate. The amount of salt (in pounds) in the barrel at time t (in minutes) is given by Q(t) = 15(1 − e−kt) where k 0.

Find k if there are 8.5 pounds of salt in the barrel after 20 minutes. Solve for k exactly and then give your answer to 4 decimal places.

Question

A 50-gallon barrel is filled completely with pure water. Salt water with a concentration of 0.3 pounds/gallon is then pumped into the barrel, and the resulting mixture overflows at the same rate. The amount of salt (in pounds) in the barrel at time t (in minutes) is given by    Q(t) = 15(1 − e−kt) where   k > 0.

Find k if there are 8.5 pounds of salt in the barrel after 20 minutes. Solve for k exactly and then give your answer to 4 decimal places.

zepdrix · Answer

Is there an exponent in that Q(t) equation somewhere? Like this?$$\Large Q(t) \quad=\quad 15(1-e^{-kt})$$

anonymous · Answer

I know i use this equation but how do i find k?

goformit100 · Answer

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