# Ratios and Proportions / Intro to Rates

Activity 2 of 15
This lesson helps students to understand that every ratio has an associated unit rate. Unit rates are important in understanding slope as a rate of change and as a problem-solving strategy for finding solutions to problems involving proportional relationships.

## Planning and Resources

Objectives
Students should understand and be able to identify the unit rate associated with a ratio. They should recognize that equivalent ratios have the same unit rate.

Vocabulary
rate
unit rate

Standard:

## Lesson Snapshot

#### Understanding

Students develop the concept of a unit rate and how to use it to compare amounts in given different ratios.

### What to look for

As students explore unit rates, remind them that to find equivalent ratios, they must multiply or divide both terms of the ratio by the same positive number.

### Sample Assessment

It took 7 hours to mow 4 lawns, each with about the same area.

a. What is the rate at which lawns were being mowed?
Answer: (7/4) hours to mow one lawn or 1 and (3/4) hours per lawn.

b. How many lawns could be mowed in 35 hours?