A company operates two cafes. The total daily cost of running the two cafes is

TC = 6000 + 180x + 140y

wherexis the number of patrons in cafe one andythe number in cafe two. The total daily revenue from the two cafes is

R = 320x + 250y - 0.375x2 - 0. 5y2 - 0.25xy

Determine the level of patronage required to maximise total profit. How much are these profits?