Lesson 14: Practice Problems

Problem 1

For each problem, explain or show your reasoning.

  1. 160 is what percentage of 40?

  2. 40 is 160% of what number?

  3. What number is 40% of 160?

Problem 2

A store is having a 20%-off sale on all merchandise. If Mai buys one item and saves $13, what was the original price of her purchase? Explain or show your reasoning.

Problem 3

The original price of a scarf was $16. During a store-closing sale, a shopper saved $12 on the scarf. What percentage discount did she receive? Explain or show your reasoning.

Problem 4

Select all the expressions whose value is larger than 100.

  1. 120% of 100

  2. 50% of 150

  3. 150% of 50

  4. 20% of 800

  5. 200% of 30

  6. 500% of 400

  7. 1% of 1,000

Problem 5 From Unit 3 Lesson 8

An ant travels at a constant rate of 30 cm every 2 minutes.

  1. At what pace does the ant travel per centimeter?

  2. At what speed does the ant travel per minute?

Problem 6 From Unit 3 Lesson 4

Is 3 cups more or less than 1 liter? Explain or show your reasoning. (Note: 1 cup 236.6 milliliters)

Problem 7 From Unit 3 Lesson 2

Name a unit of measurement that is about the same size as each object.

  1. The distance of a doorknob from the floor is about 1 .

  2. The thickness of a fingernail is about 1 .

  3. The volume of a drop of honey is about 1 .

  4. The weight or mass of a pineapple is about 1 .

  5. The thickness of a picture book is about 1 .

  6. The weight or mass of a buffalo is about 1 .

  7. The volume of a flower vase is about 1 .

  8. The weight or mass of 20 staples is about 1 .

  9. The volume of a melon is about 1 .

  10. The length of a piece of printer paper is about 1 .