IMSA Ratios, Proportions, and Percentages 1 — Questions and Answers
Question 1: A recipe calls for 3 cups of flour for every 2 cups of sugar. If you use 9 cups of flour, how many cups of sugar do you need?
- 4
- 6 (Correct answer)
- 5
- 8
Correct answer: 6
Setting up the proportion 3/2 = 9/x and cross-multiplying gives x = 6.
Question 2: What is 35% of 280?
- 98 (Correct answer)
- 84
- 112
- 91
Correct answer: 98
35% of 280 = 0.35 × 280 = 98.
Question 3: A jacket sells for $120 after a 20% discount. What was the original price?
- $144
- $96
- $150 (Correct answer)
- $140
Correct answer: $150
If $120 is 80% of the original price, then original = 120 ÷ 0.80 = $150.
Question 4: The ratio of boys to girls in a class is 3:4. If there are 28 girls, how many boys are there?
- 18
- 21 (Correct answer)
- 24
- 12
Correct answer: 21
Using the proportion 3/4 = x/28, cross-multiplying gives x = 21 boys.
Question 5: If 5 workers can complete a job in 12 days, how many days will 10 workers take to complete the same job?
- 8
- 6 (Correct answer)
- 4
- 10
Correct answer: 6
This is an inverse proportion: 5 × 12 = 10 × x, so x = 6 days.
Question 6: A car travels 240 miles using 8 gallons of gas. At the same rate, how many gallons are needed to travel 360 miles?
- 10
- 14
- 12 (Correct answer)
- 16
Correct answer: 12
The rate is 30 miles/gallon, so 360 ÷ 30 = 12 gallons.
Question 7: A price increased from $50 to $65. What is the percent increase?
- 25%
- 15%
- 30% (Correct answer)
- 20%
Correct answer: 30%
Percent increase = (65 − 50) / 50 × 100 = 15/50 × 100 = 30%.
IMSA Ratios, Proportions, and Percentages 1
A recipe calls for 3 cups of flour for every 2 cups of sugar.
If you use 9 cups of flour, how many cups of sugar do you need?