PSAT Math Multiple-Choice Question 542: Answer and Explanation

Question: 542

Including the flat fee for the phone charger and the sales tax, Maria will need to pay a total of $685.72 for the cell phone. How much is the purchase price of the cell phone, to the nearest dollar?

• A. $750
• B. $659
• C. $625
• D. $622

Correct Answer: C

Explanation:

C

The question asks for the purchase price of the cell phone to the nearest dollar. Start by ballparking. The purchase price does not include the tax or the flat fee for the phone charger, so the purchase price must be less than the actual total paid. Eliminate (A), as it is not less than the total of $685.72 paid for the cell phone. Since the question asks for a specific value and the answers contain numbers in decreasing order, plug in the answers. Begin by labeling the answers as "purchase price" and start with (C), $625. The question states that the cell phone will have a 6.5% sales tax on the purchase price. "Percent" means divide by 100. Then multiply the result by the value of which the percent is taken. This becomes 0.065($625) = $40.625. Add this to $625 to get $665.63. The question also states that a flat fee of $20 is added for the phone charger, so this becomes $665.63 + $20 = $685.63. This nearly matches the value given in the question, which asks for the price to the nearest dollar, so stop here. The correct answer is (C).