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)

Question

phoenixfire · Answer

For (a) I got $$V(t) = 10 - t$$

phoenixfire · Answer

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.

turingtest · Answer

oh that language filter, lol