Del Michaels Had a Successful Morning, or So He Thinks

Short Answer

Del Michaels had a successful morning, or so he thinks, selling 1300 surplus notebook computers over the telephone to three commercial customers. The three customers were not equally skillful at negotiating a low unit price. Customer A bought 600 computers for $1252 each, B bought 300 units at $1310 each, and C bought 400 at $1375 each.
A) What is the average unit price at which Del sold the 1300 computers?
B) Del's manager told Del he expected him to sell, by the end of the day, a total of 2500 surplus computers at an average price of $1312 each. What is the average unit price at which Del must sell the remaining 1200 computers?