Customary Unit Conversion Factors
Customary unit conversion factors are a Grade 6 math skill in Reveal Math, Course 1. The US customary system uses units like inches, feet, yards, miles for length; ounces, pounds, tons for weight; cups, pints, quarts, gallons for liquid volume; and seconds, minutes, hours, days for time. Converting between units requires multiplying or dividing by the appropriate conversion factor. For example, 1 foot = 12 inches, 1 yard = 3 feet, 1 mile = 5,280 feet. Knowing these key conversion factors and applying them correctly — multiplying when going to a smaller unit, dividing when going to a larger unit — is essential for applied measurement problems.
Key Concepts
A conversion factor is a ratio of two equivalent measurements. Because the two quantities represent the same amount, a unit ratio (conversion factor) is essentially equal to 1. Multiplying by this ratio changes the unit but not the actual underlying value.
Below are common conversion factors for the customary system:.
Common Questions
What are the main customary unit conversion factors?
Length: 1 ft = 12 in, 1 yd = 3 ft, 1 mi = 5,280 ft. Weight: 1 lb = 16 oz, 1 ton = 2,000 lb. Liquid volume: 1 pt = 2 cups, 1 qt = 2 pt, 1 gal = 4 qt. Time: 1 min = 60 sec, 1 hr = 60 min.
How do you convert from a larger unit to a smaller unit in the customary system?
Multiply by the conversion factor. To convert 3 feet to inches: 3 x 12 = 36 inches. Going to a smaller unit means you have more of them, so multiply.
How do you convert from a smaller unit to a larger unit?
Divide by the conversion factor. To convert 48 ounces to pounds: 48 / 16 = 3 pounds. Going to a larger unit means you have fewer of them, so divide.
Why do students need to know customary conversion factors?
The US customary system is still widely used in everyday American life for cooking, construction, sports, and navigation. Students need fluency with these units for real-world problem solving and standardized tests.
How is customary unit conversion different from metric conversion?
Metric conversion uses powers of 10 (10, 100, 1000) between units, making it simpler to compute. Customary conversions use irregular factors (12, 3, 5280, 16, etc.) that must be memorized.
When do students learn customary unit conversion?
Customary unit conversion is a Grade 6 topic in Reveal Math, Course 1, in the measurement and ratio unit. Students use conversion factors as ratios to set up proportions.
Which textbook covers customary unit conversion factors?
Reveal Math, Course 1, used in Grade 6, covers customary conversions in the ratios and measurement chapter.