Answer:
$29.96
Explanation:
You want the total cost of $28 for shirts, with a 7% tax added.
Tax
The tax amount is the product of the sale value and the tax rate:
tax = $28 × 0.07 = $1.96
Total cost
The total cost is the sum of the sale value and the tax:
total cost = $28 + 1.96
total cost = $29.96
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Additional comment
The math can be simplified to the product ...
total cost = (sale value) × (1 +tax rate) = $28 × 1.07 = $29.96