1200 cases are to be sold in the year, ordering costs are and carrying costs are . Find the order size that will minimize inventory cost (economic order quantity) x is the order quantity. r is the number of orders placed. c is the inventory cost. Objective equation is c = 75r+8 x/2 make the objective equation in terms of x. Constraint equation: r x = 1200, r = 1200/x by substituting the r into it. 4=90,000 4x2 = 90,000 (cid:1876) 2= (cid:1877), however we reject the negative. C = 90,000+4x c" = -90,000+4 find the derivative. x x2. 150: rancher has 204 meters in fencing, building two corrals: one square, one rectangular with length that is twice the width. Find the dimensions that result in the greatest combined area. See textbook: starting with a 40 foot-long stone wall, farmer wants to construct a rectangular enclosure by adding 240 feet of fence.