Lesson 1

Using Decimals in a Shopping Context

Let’s use what we know about decimals to make shopping decisions.

Problem 1

Mai had $14.50. She spent$4.35 at the snack bar and $5.25 at the arcade. What is the exact amount of money Mai has left? A:$9.60

B:

$10.60 C:$4.90

D:

Problem 4

Chicken costs $3.20 per pound, and beef costs$4.59 per pound. Answer each question and show your reasoning.

1. What is the exact cost of 3 pounds of chicken?

2. What is the exact cost of 3 pound of beef?

3. How much more does 3 pounds of beef cost than 3 pounds of chicken?

Problem 5

1. How many $$\frac15$$-liter glasses can Lin fill with a $$1 \frac12$$-liter bottle of water?
2. How many $$1 \frac12$$-liter bottles of water does it take to fill a 16-liter jug?
(From Unit 4, Lesson 16.)

Problem 6

Let the side length of each small square on the grid represents 1 unit. Draw two different triangles, each with base $$5\frac12$$ units and area $$19\frac14$$ units2.

Why does each of your triangles have area $$19\frac14 \text{ units}^2$$? Explain or show your reasoning.

(From Unit 4, Lesson 14.)

Problem 7

Find each quotient.

1. $$\frac56 \div \frac16$$
2. $$1\frac16 \div \frac{1}{12}$$
3. $$\frac{10}{6 }\div \frac{1}{24}$$
(From Unit 4, Lesson 10.)