Answer:
The cost of each cotton candy bag is $4.
Step-by-step explanation:
Consider the provided information.
Let, the vendor has dollar at the starting of each day.
Let, the cost of each cotton candy bag is .
Now when she sells a total of 12 bags, she has $128.
.....(1)
After she sells a total of 20 bags, she has $160.
....(2)
Subtract equation 1 from equation 2.
Hence, the cost of each cotton candy bag is $4.