Drill 3 · Math · Ratios, Rates, and Percents
SAT Math: Ratios, Rates, and Percents (Drill 3) is a Math practice drill covering Ratios, Rates, and Percents. It contains 5 original questions created by Brian Stewart, a Barron's test prep author with over 20 years of tutoring experience.
SAT ratio, rate, and percent questions test proportional reasoning, multi-step percent calculations, unit conversions using dimensional analysis, combined work rates, and applying percent concepts to real-world scenarios involving markups, discounts, and compound changes.
Question 1. A shirt originally priced at $60 is marked up by 25%, then the new price is discounted by 20%. What is the final price?
Explanation: After 25% markup: $60 × 1.25 = $75. After 20% discount: $75 × 0.80 = $60. The final price equals the original, but this is coincidental, not guaranteed for all markup/discount pairs.
Question 2. Machine A produces 120 widgets per hour and Machine B produces 80 widgets per hour. Working together, how many minutes will it take them to produce 500 widgets?
Explanation: Combined rate = 200 widgets/hour. Time = 500/200 = 2.5 hours = 150 minutes.
Question 3. The ratio of boys to girls in a class is 3:5. If there are 40 students total, how many are boys?
Explanation: 3 + 5 = 8 parts. Each part = 40/8 = 5 students. Boys = 3 × 5 = 15.
Question 4. A car travels 240 miles on 8 gallons of gas. At this rate, how many gallons are needed for a 450-mile trip?
Explanation: Rate = 240/8 = 30 miles per gallon. Gallons needed = 450/30 = 15.
Question 5. A town's population decreased from 25,000 to 22,000. What is the percent decrease?
Explanation: Change = 25,000 − 22,000 = 3,000. Percent decrease = 3,000/25,000 × 100 = 12%.