Hello, I am trying to tackle a word problem in differential equations, but the setup has flummoxed me. Thank you in advance to any advice/help given. 1. The problem statement, all variables and given/known data Beginning at time t 0, fresh water is pumped at the rate of 3 gal/min into a 60-gal tank initially filled with brine. The resulting less-and-less salty mixture overflows at the same rate into a second 60-gal tank that initially contained only pure water, and from there it eventually spills onto the ground. Assuming perfect mixing in both tanks, when will the water in the second tank taste saltiest? And exactly how salty will it then be, compared with the original brine? 2. Relevant equations ds/dt = input - output du/dt = previous output - output 3. The attempt at a solution I have included a picture of a scratch piece of paper I am working on to demonstrate my work.