Question

The total cost to buy 12 balloons was $4. The total cost to buy 19 balloons was $6. What was the average cost of the balloons

Answer 1

the average cost of balloons is $3

Answer 2

average cost=total number of balloons/total cost=
total number=12+19=31
total cost=4+6=10

so average cost=31/10=3.1

the average cost was $3.10 per ballon