Question 4 1 pt A farmer estimates that if he picks his corn
     Question 4 1 pt A farmer estimates that if he picks his corn now his fields will yield 170 bushels per acre at a wholesale price of $4.2 per bushel. Each day he delays picking, he estimates his crop will increase by 3.8 bushels per acre, but the price will drop $0.05 per bushel. How many days should he delay picking to maximize the revenue he earns from his corn crop? Express your answer in days to the nearest whole day  
  
  Solution
Let t is the time from present
Volume of bushels at any time =170+3.8t
Price at any time =$(4.2-0.05t)
Total revenue =(170+3.8t)*(4.2-0.05t) =714+15.96t-8.5t-0.19t2 =-0.19t2 +7.46t +714
Let us take the first derivate of above equation w.r.t and keeping it equal to zero
dTCR/dt =-0.38t+7.46=0
t=19.63=20 days
so the answer is 20 days

