SAT Math Multiple Choice Question 91: Answer and Explanation
1. Bryan, who works in a high-end jewelry store, earns a base pay of $10.00 per hour plus a certain percent commission on the sales that he helps to broker in the store. Bryan worked an average of 35 hours per week over the past two weeks and helped to broker sales of $5,000.00 worth of jewelry during that same two-week period. If Bryan's earnings for the two-week period were $850.00, what percent commission on sales does Bryan earn?
- A. 1%
- B. 2%
- C. 3%
- D. 4%
Correct Answer: C
C There are a few different ways to approach this question. In any approach, the best first step is to figure out how much income Bryan earned during the two-week period without the commission. Since he worked an average of 35 hours per week for two weeks, he worked a total of 70 hours. At a rate of $10.00 per hour base pay, this would add up to $700.00 (70 × 10 = 700). Since Bryan's earnings were actually $850.00, that means he must have earned $150.00 of commission (850 - 700 = 150). At this point, you can calculate the percent commission algebraically or simply work backwards from the answers. Algebraically, you know that $150.00 is equal to a certain percent of $5,000.00 in sales, which can be represented as follows: 150 = (5,000). Solve for x, and you get 3, which is (C). If instead you wish to work backwards from the answers, you can take the answers and calculate what 1%, 2%, etc. of $5,000.00 would be, and then add that back to $700.00 to see which choice matches your target of $850.00: (C).