The total amount of Cassie's purchase can be calculated by adding the cost of the shoes and the shirt, and then adding the tax.
The cost of the shoes and the shirt is:
16.50 + 8.50 = 25.00
To calculate the tax, we need to multiply the cost of the items by the tax rate (as a decimal):
25.00 × 0.08 = 2.00
So the tax on the purchase is $2.00.
To find the total amount of the purchase, we add the cost of the items to the tax:
25.00 + 2.00 = 27.00
Therefore, the total amount of Cassie's purchase will be $27.00.