- #1

yecko

Gold Member

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## Homework Statement

A tank originally contains 100 gal of fresh water. Then water containing 1/2 lb of salt per gallon is poured into the tank at a rate of 2 gal/min, and the mixture is allowed to leave at the same rate. After 10 min the process is stopped, and fresh water is poured into the tank at a rate of 2 gal/min, with the mixture again leaving at the same rate. Find the amount salt in the tank at the end of an additional 10 min.

How can the two highlighted part obtain?

## Homework Equations

y(t)=(1/μ(t)) ∫

*{from to to t}*[yoμo+∫(g(t)μ(t))dt]

## The Attempt at a Solution

I have tried to substitute the formula, S1(t)=e^(-0.02t) * ∫

*{from 0 to t}*(S1(t)/50)e^(0.02t) dt

which seems wrong...

Thanks

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