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PhoenixFire
When mixing a certain "alcoholic beverage" a barperson starts with a 10 litre solution of 20% alcohol. Into this solution the barperson mixes a 40% mixture at the rate of 1 litre/minute and pours into glasses at the rate of 2 litre/minute. (a) Find a formula for the volume V(t) of the mixture at time t minutes. (b) Find a differential equation that tells the rate of change of the amount of alcohol A(t) at time t minutes. (c) Solve the differential equation and use the initial condition to find a formula for A(t)
For (a) I got \[V(t) = 10 - t\]
I can't figure out (b).... I tried \[{\delta A \over \delta t}=0.2(10-t)+0.4t-2t{A \over {10-t}}\] But I don't know if that's right. Please help.
oh that language filter, lol