IMSA Ratios, Proportions, and Percentages

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?

Accepted Answer

6

Answer

Setting up the proportion 3/2 = 9/x and cross-multiplying gives x = 6.

Question 2

What is 35% of 280?

Accepted Answer

98

Answer

35% of 280 = 0.35 × 280 = 98.

Question 3

A jacket sells for $120 after a 20% discount. What was the original price?

Accepted Answer

$150

Answer

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?

Accepted Answer

21

Answer

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?

Accepted Answer

6

Answer

This is an inverse proportion: 5 × 12 = 10 × x, so x = 6 days.

IMSA - Intermediate Math Skill Assesment Practice Test