Step 1: $3.30 X 4 boxes = $13.20
Step 2: $13.20 X 1.04 (4% tax) = 13.728 (1.04 = 1 + .04 (1 to get the cost, and .04 for 4/100 tax)
The total with tax would be $13.73 (Rounded to the nearest cent)
Assignment: Write your own tax problem. Include the cost of the product. Find out how much the item would cost after a 4% tax is included.