In this question it is important to note down all the important information's that are mentioned in the question.
Cost of a container of cat liter = $13.75
Cost of a bag of cat food = X dollars
Total amount of money required to purchase the items = $20.80
Percentage of sales tax that had to be given = 4%
Then
Amount of sales tax given = (4/100) * 20.8 dollars
= 20.8/25 dollars
= 0.83 dollars
Then the total purchase price for the two items = 20.80 - 0.83 dollars
= 19.97 dollars
Now we can easily find the cost of the cat food by subtracting the cost of the liter from the total purchase amount.
Then
Cost of the cat food = 19.97 - 13.75 dollars
= 6.22 dollars
So the cost of the bag of cat food is $6.22
