A produce person took a total of 3000 bags of potatoes to auction. Of the 3000 bags, 40 bags were spoiled and were dumped prior to the sale. 960 bags were sold for $6.75 per bag; 1100 bags for $6.25 per bag; 500 bags for $7.15 per bag; and the remainder for $7.10 per bag. What was the average price per bag?