Lesson 3.10Convert Measurement Units
Start hereWords, worked example, and sentence starters
Learning target I can convert measurement units using ratios and conversion factors.
Start hereWords for this lesson
Read each word before you begin. Say it out loud.
| Word | What it means | Example |
|---|---|---|
| Conversion FactorSpanish: Factor de conversión | A ratio that helps you change one unit into another. | 1 foot = 12 inches, so the factor is 12 |
| UnitSpanish: Unidad | A standard amount used to measure, like an inch or a liter. | Inches, feet, pounds, ounces |
| EquivalentSpanish: Equivalente | Having the same value, just in different units. | 2 feet = 24 inches |
| RatioSpanish: Razón | A way to compare two amounts, like 3 to 2. | 12 inches per 1 foot |
| Customary unitsSpanish: Unidades usuales (sistema inglés) | The U.S. way of measuring, like inches, feet, and pounds. | 12 inches = 1 foot, 3 feet = 1 yard, 16 ounces = 1 pound |
| Metric unitsSpanish: Unidades métricas | A way of measuring by 10s, like meters, liters, and grams. | 1 meter = 100 centimeters, 1 kilogram = 1,000 grams |
How it worksWorked example
These numbers are not on your problems. The steps are. Follow them with your own numbers.
The cabinet is 5 feet tall. I want to know how many inches that is.
- My conversion factor is 1 foot = 12 inches.
- Inches are smaller than feet, so I multiply: 5 × 12 = 60.
- So 5 feet = 60 inches.
Now you trySame steps, your turn
The steps are the same as the worked example. The numbers are yours. Do the work.
A wire is 4 yards long. The factor is 1 yard = 3 feet.
Say it and write itSentence starters
Finish each sentence out loud with a partner. Then use them in your writing.
- When converting from a unit to a unit, I by the conversion factor because .
Word bank Conversion FactorUnitEquivalentRatioCustomary unitsMetric unitslargersmallermultiplydivideconversion factorratio
Watch outA common mistake
A common mistake in Convert Measurement Units is applying the conversion factor in the wrong direction — for example, converting 4 feet to inches by dividing (4 ÷ 12 = 0.33 inches) instead of multiplying (4 × 12 = 48 inches), or converting 80 ounces to pounds by multiplying (80 × 16 = 1,280 pounds) instead of dividing (80 ÷ 16 = 5 pounds). Before you answer, ask: am I changing to a SMALLER unit (there will be MORE of them, so multiply) or a BIGGER unit (there will be FEWER of them, so divide)?
Lesson 3.10Convert Measurement Units
Version ASupported practice
Learning target I can convert measurement units using ratios and conversion factors.
-
1Complete the table. Show how you found each value.
Complete the conversion table using the given conversion factors.
Given Conversion Factor Answer 2 feet 1 ft = 12 in 24 inches 6 yards 1 yd = 3 ft 3 pounds 1 lb = 16 oz Hint Each row hands you the conversion factor — the finished row shows 2 feet × 12 = 24 inches.
Show your work
-
2Circle the letter of the best answer. Show how you know.
How many inches are in 7 feet?
- A70 inches
- B72 inches
- C84 inches
- D96 inches
Hint The key fact: 1 foot = 12 inches. You have 7 feet and want inches.
Show your work -
3Circle the letter of the best answer. Show how you know.
How many feet are in 3 yards?
- A6 feet
- B9 feet
- C12 feet
- D36 feet
Hint The key fact: 1 yard = 3 feet. You have 3 yards and want feet.
Show your work -
4Circle the letter of the best answer. Show how you know.
How many ounces are in 4 pounds?
- A16 ounces
- B32 ounces
- C48 ounces
- D64 ounces
Hint The key fact: 1 pound = 16 ounces. You have 4 pounds and want ounces.
Show your work -
5Circle the letter of the best answer. Show how you know.
Convert 24 inches to feet.
- A2 feet
- B3 feet
- C12 feet
- D24 feet
Hint This one goes the OTHER direction: inches (small) to feet (big), so the number of units gets smaller.
Show your work
-
6Find the mistake. Explain it, then show the correct work.
Spot the Common Mistake
- 1Convert 2 yards of rope to feet2 yards → feet
- 2Use the conversion factor1 yard = 3 feet
- 3Operate2 ÷ 3 = 0.67 feet
- 4Final answer2 yards ≈ 0.67 feet
Which step has the mistake? Explain what went wrong, then show the correct work.
Hint You are going from a bigger unit (yards) to a smaller unit (feet). Should the number get bigger or smaller?
Correct workCorrect answer:
Explain your thinkingHow do you decide whether to multiply or divide when converting units?
Sentence starter When converting from a ___ unit to a ___ unit, I ___ by the conversion factor because ___.
Lesson 3.10Convert Measurement Units
Version BCore practice
Learning target I can convert measurement units using ratios and conversion factors.
-
1Write the letter of the matching item on each line.
Match each measurement to its equivalent value.
- 3 yards
- 4 feet
- 5 pounds
- 2 yards
- 36 inches
- 3 pounds
- A9 feet
- B48 inches
- C80 ounces
- D72 inches
- E3 feet
- F48 ounces
-
2Complete the table. Show how you found each value.
An arcade cabinet has parts measured in different units. Convert each to the target unit.
Part Measurement Target Unit Converted Power cord 2 yards inches Top panel 54 inches feet Weight 96 ounces pounds Side rail 5 feet inches Show your work -
3Write the name of the correct group on each line.
When converting, do you multiply or divide? Sort each conversion by the correct operation.
- Feet → inches
- Yards → feet
- Pounds → ounces
- Inches → feet
- Ounces → pounds
- Feet → yards
-
4Circle the letter of the best answer. Show how you know.
A shelf is 30 inches long. How many feet and inches is that?
- A1 foot 18 inches
- B2 feet 6 inches
- C2 feet 8 inches
- D3 feet 0 inches
Show your work
-
5Find the mistake. Explain it, then show the correct work.
Spot the Common Mistake
- 1Convert 80 ounces of bolts to pounds80 ounces → pounds
- 2Use the conversion factor1 pound = 16 ounces
- 3Operate80 × 16 = 1,280 pounds
- 4Final answer80 ounces = 1,280 pounds
Which step has the mistake? Explain what went wrong, then show the correct work.
Correct workCorrect answer:
Explain your thinkingHow do you decide whether to multiply or divide when converting units?
Lesson 3.10Convert Measurement Units
ChallengeExtension
Learning target I can convert measurement units using ratios and conversion factors.
-
1Mark and label each value on the number line.
Place these lengths on a number line in inches: A = 1 foot, B = 1.5 feet, C = 2 feet, D = 1 yard
Show your thinking
-
2Find the mistake. Explain it, then show the correct work.
Find the Conversion Error
- 1Convert 6 feet to yards6 feet → yards
- 2Use conversion factor1 yard = 3 feet
- 3Multiply6 × 3 = 18 yards
- 4Final answer6 feet = 18 yards
Which step has the mistake? Explain what went wrong, then show the correct work.
Correct workCorrect answer: -
3Answer in complete sentences.
A recipe says you need 5 feet of ribbon, but the store only sells ribbon in inches. Another recipe says you need 2 yards of fabric, but your ruler measures in feet. Convert both measurements and explain the steps you used. Which conversion factor did you use each time?
Write your answer