9514 1404 393
Answer:
a = $0.95
Explanation:
The cost of a sharpener is 'a', and the cost of a folder is $2.80 more, so is a+2.80. The total cost of 4 sharpeners and 7 folders is ...
4a +7(a+2.80) = 30.05
11a = 10.45 . . . . . . . . . . . subtract 19.60
a = 0.95 . . . . . . . . . . . divide by 11
The cost of a sharpener is a = $0.95.