PSAT Math Multiple-Choice Practice Question 593

Correct Answer: B

Explanation:

(B) The cost of the sales tax on the good is found by subtracting the untaxed price from the total cost:

1.07P - P = 0.07P

You can also visualize this by plugging in a sample value for the price of the good. A helpful sample value to use with percentages is 100 since it gives easily understood results. If, for example, you suppose that the price of the good is $100, the cost with the sales tax included is 1.07 × $100 = $107. So the sales tax on the good is $107 - $100 = $7. This is equivalent to 0.07 × $100 = $7.