# Converting Measurement Units

Students will learn how to use ratio reasoning to convert measurement units.

## Lesson Objective

The lesson is aligned to the Common Core State Standards for Mathematics – 6.RP.3.d Ratios and Proportional Relationships – Use ratio reasoning to convert measurement units; manipulate and transform units appropriately when multiplying or dividing quantities.

## Lesson Procedure:

**Use ratios to convert the measurement units.**

A ratio can be written to show the relationship between inches and centimeters.

1 inch = 2.54 centimeters

This can be written as a ratio of inch to centimeters.

1 to 2.54

1 : 2.54

1/2.54

1. Complete the table to show four inches is equal to the number of centimeters.

2. How many centimeters equal 4 inches?

3. Explain how you found your answer.

A ratio can be written to show the relationship between miles and kilometers.

1 mile = 1.6 kilometers

This can be written as a ratio of mile to kilometers.

1 to 1.6

1 : 1.6

1/1.6

4. Complete the table to show five miles is equal to the number of kilometers.

5. How many kilometers equal 5 miles?

6. Explain how you found your answer.

**Answers:**

- Complete the table.
- Multiply 1 x 4 = 4, so multiply 2.54 x 4 = 10.16.
- 4 inches equal 10.16 centimeters
- Complete the table.
- Multiply 1 x 5 = 5, so multiply 1.6 x 5 = 8.
- 5 miles equal approximately 8 kilometers

## Individual or Group Work

**Use ratios to solve problems involving measurement conversion. **

**1 pound equals approximately 0.454 kilograms**

- Write the ratio to show the relationship between pounds and kilograms.
- Approximately, how many kilograms are equal to 16 pounds? 7.264 kilograms
- Approximately, how many kilograms are equal to 8 pounds? 3.632 kilograms

**1 foot equals approximately 0.305 meters**

- Write the ratio to show the relationship between feet and meters.
- Approximately, how many meters are equal to 7 feet? 2.135 meters
- Approximately, how many meters are equal to 14 feet? 4.27 meters

**1 mile equals 5,280 feet**

- Write the ratio to show the relationship between miles and feet.
- How many feet are equal to 26 miles? 137,280 feet
- How many feet are equal to 15 miles? 79,200 feet

**1 yard equals 36 inches**

- Write the ratio to show the relationship between yards and inches.
- How many inches are equal to 3 yards? 108 inches
- How many inches are equal to 5 yards? 180 inches

**Answers:**

**1 pound equals approximately 0.454 kilograms**

- pounds to kilograms, 1 to 0.454, 1 : 0.454, 1/0.454
- 7.264 kilograms
- 3.632 kilograms

**1 foot equals approximately 0.305 meters**

- feet to meters, 1 to 0.305, 1 : 0.305, 1/0.305
- 2.135 meters
- 4.27 meters

**1 mile equals 5,280 feet**

- miles to feet, 1 to 5,280m 1 : 5,280, 1/5,280
- 137,280 feet
- 79,200 feet

**1 yard equals 36 inches**

- yards to inches, 1 to 36, 1 : 36, 1/36
- 108 inches
- 180 inches