Lola bought 25 bottles of oil.the average cost of 12 bottles of oil was $28. The total cost of the other 13 bottles was $442. (A) Find the total cost of the 25bottles of oil
b) find the average cost of the 25 bottles of oil,
Please help 
+36916 Total cost ==== 12 bottles x $28/bottle + $442 = $778
Average overall= total cost/#bottles = 778/25 = $ 31.12 per bottle
