Ivanhoe Company uses a perpetual inventory system. Data for product E2-D2 includes the following purchases. Date Number of Units Unit Price May 7 40 $12 July 28 30 17 On June 1, Ivanhoe sold 20 units, and on August 27, 30 more units. (a) Your answer is incorrect. Calculate the average cost of the goods sold in the sale. (Round answers to 3 decimal places, e.g. 5.125.) June 1 sale: $ Aug. 27 sale: $