Each of the two tanks contains 400 gal of water, in which initially 100 lb (Tank T1)

Question:

Each of the two tanks contains 400 gal of water, in which initially 100 lb (Tank T1) and 40 lb (Tank T2) of fertilizer are dissolved. The inflow, circulation, and outflow are shown in Fig. 87. The mixture is kept uniform by stirring. Find the fertilizer contents y1 (t) in T1 and y2 (t) inT2.