Lesson 8: Practice Problems

Problem 1

In 2016, the cost of 2 ounces of pure gold was $2,640. Complete the double number line to show the cost for 1, 3, and 4 ounces of gold.

A double number line with 6 evenly spaced tick marks. The top number line is labeled “cost in dollars;” the first tick mark is labeled 0, the third tick mark is labeled 2,640 and the sixth tick mark is labeled 6600. The bottom number line is labeled “ounces of gold” and starting with the first tick mark 0, 1, 2, 3, 4, 5, and 6 are labeled.

Problem 2

The double number line shows that 4 pounds of tomatoes cost $14. Draw tick marks and write labels to show the prices of 1, 2, and 3 pounds of tomatoes.

A double number line with one tick mark at the beginning of the line and one at the end. The top number line is labeled “pounds of tomatoes” with the first tick mark labeled 0 and the last tick mark labeled 4. The bottom number line is labeled “cost in dollars” with the first tick mark labeled 0 and the last tick mark labeled 14.

Problem 3

4 movie tickets cost $48. At this rate, what is the cost of:

  1. 5 movie tickets?

  2. 11 movie tickets?

Problem 4

Priya bought these items at the grocery store. Find each unit price.

  1. 12 eggs for $3. How much is the cost per egg?

  2. 3 pounds of peanuts for $7.50. How much is the cost per pound?

  3. 4 rolls of toilet paper for $2. How much is the cost per roll?

  4. 10 apples for $3.50. How much is the cost per apple?

Problem 5 From Unit 2 Lesson 3

Clare made a smoothie with 1 cup of yogurt, 3 tablespoons of peanut butter, 2 teaspoons of chocolate syrup, and 2 cups of crushed ice.

  1. Kiran tried to double this recipe. He used 2 cups of yogurt, 6 tablespoons of peanut butter, 5 teaspoons of chocolate syrup, and 4 cups of crushed ice. He didn’t think it tasted right. Describe how the flavor of Kiran’s recipe compares to Clare’s recipe.

  2. How should Kiran change the quantities that he used so that his smoothie tastes just like Clare’s?

Problem 6 From Unit 1 Lesson 15

A drama club is building a wooden stage in the shape of a trapezoidal prism. The height of the stage is 2 feet. Some measurements of the stage are shown here.

A drawing of a 3-D trapezoid prism and another drawing showing the trapezoid face. Both drawings show measurements.

What is the area of all the faces of the stage, excluding the bottom? Show your reasoning. If you get stuck, consider drawing a net of the prism.