Answer:
$42
Explanation:
You want the price with tax of a $35 pair of shoes subject to a 20% tax.
Price with tax
The tax is the cost of the shoes multiplied by the tax rate. The final price is the sum of the cost of the shoes and the tax:
final price = price + price × tax rate
final price = price × (1 + tax rate) = $35 × 1.20 = $42
The final price of the shoes is $42.