# Lesson 9

Solving Rate Problems

Let's use unit rates like a pro.

### Problem 1

This package of sliced cheese costs $2.97.

How much would a package with 18 slices cost at the same price per slice? Explain or show your reasoning.

### Problem 2

A copy machine can print 480 copies every 4 minutes. For each question, explain or show your reasoning.

- How many copies can it print in 10 minutes?
- A teacher printed 720 copies. How long did it take to print?

### Problem 3

Order these objects from heaviest to lightest.

(Note: 1 pound = 16 ounces, 1 kilogram \(\approx\) 2.2 pounds, and 1 ton = 2,000 pounds)

item | weight |
---|---|

school bus | 9 tons |

horse | 1,100 pounds |

elephant | 5,500 kilograms |

grand piano | 15,840 ounces |

### Problem 4

Andre sometimes mows lawns on the weekend to make extra money. Two weeks ago, he mowed a neighbor’s lawn for \(\frac{1}{2}\) hour and earned $10. Last week, he mowed his uncle’s lawn for \(\frac{3}{2}\) hours and earned $30. This week, he mowed the lawn of a community center for 2 hours and earned $30.

Which jobs paid better than others? Explain your reasoning.

### Problem 5

Calculate and express your answer in decimal form.

- \(\frac12 \boldcdot 17\)
- \(\frac34 \boldcdot 200\)
- \((0.2) \boldcdot 40\)
- \((0.25) \boldcdot 60\)

### Problem 6

Here is a polygon.

- Decompose this polygon so that its area can be calculated. All measurements are in centimeters.
- Calculate its area. Organize your work so that it can be followed by others.