Each year, 11% of the water in Lake Huron flows into Lake Erie and an aluminium factory on Lake Huron pumps 25 tons of pollutant into the lake each year. Presently, there are 3500 tons of this pollutant dissolved in the lake. Use a differential equation to model the rate of change of pollutant in Lake Huron with respect to time (meausered in years), and solve the differential equation for the level of pollutant in Lake Huron during any given year using the initial condition P(0)=3500.

I really would just love for some one to set up the differential equation for this problem, I should be able to take it from there.