(adsbygoogle = window.adsbygoogle || []).push({}); There is a tank that contains 10,000 gallons of a weak salt solution. The salt concentration is 1300 parts per million. Now we start adding 130 gallons per minute of water and also remove 130 gallons per minute of salt solution. Thererore the salt solution concentration gradually decreases to zero parts per million. Assume the tank is agitated and well mixed.

How long does it take the salt solution concentration to decrease to 100 parts per million?

How long ....... to 10 parts per million?

How long ....... to 1 part per million?

I tried a decay solution as a logarithmic function ( which I believe is not quite correct ) but couldn't come up with correct calculus method.

Can someone offer a calculus & non-calculus solution ?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Decay problem

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