In this Grade 7 Saxon Math Course 2 lesson, students learn how to use unit multipliers — fractions equal to 1 that contain equivalent measures — to convert between units of measurement such as inches to feet or feet to yards. Students practice setting up conversion problems by selecting the correct unit multiplier so that unwanted units cancel, leaving only the desired unit in the answer. This lesson connects fraction canceling and the Identity Property of Multiplication to real-world unit conversion within Chapter 5.
Section 1
📘 Unit Multipliers and Unit Conversion
Unit multipliers are fractions that have units and are equal to 1. We use them to convert from one unit of measure to another.
When we set up unit conversion problems, we will write the numbers in this order:
This is your foundation for a powerful technique called dimensional analysis. Next, you’ll apply this concept in worked examples to convert lengths, rates, and make cross-system comparisons.
Section 2
Canceling
We can apply the procedure of canceling to units as well. We may cancel units that appear in both the numerator and the denominator before we multiply.
To convert 5 feet to inches, the 'ft' units cancel out:
Think of canceling units as a magic trick! Matching units on the top and bottom of fractions get to disappear. This tidies up your problem before you even start multiplying, making conversions super clean and easy to solve without getting lost in a mess of different units. It is the key to success!
Section 3
Unit multipliers
Because these fractions have units and are equal to 1, we call them unit multipliers. For an equivalent measure like , the two unit multipliers are:
Two unit multipliers for are:
Unit multipliers are like secret identity changers for your numbers! Since they always equal 1, multiplying by them doesn’t change a value, just its name (or unit). You just need to pick the right one to switch from feet to inches, or ounces to pounds. Presto change-o!
Section 4
Converting With Unit Multipliers
When we set up unit conversion problems, we will write the numbers in this order:
Convert 240 yards to feet:
This is a simple matching game! To switch units, pick the unit multiplier that puts the unit you want on top and the unit you are getting rid of on the bottom. The old unit gets canceled out, leaving you with the shiny new unit you wanted. It's a guaranteed win!
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Section 1
📘 Unit Multipliers and Unit Conversion
Unit multipliers are fractions that have units and are equal to 1. We use them to convert from one unit of measure to another.
When we set up unit conversion problems, we will write the numbers in this order:
This is your foundation for a powerful technique called dimensional analysis. Next, you’ll apply this concept in worked examples to convert lengths, rates, and make cross-system comparisons.
Section 2
Canceling
We can apply the procedure of canceling to units as well. We may cancel units that appear in both the numerator and the denominator before we multiply.
To convert 5 feet to inches, the 'ft' units cancel out:
Think of canceling units as a magic trick! Matching units on the top and bottom of fractions get to disappear. This tidies up your problem before you even start multiplying, making conversions super clean and easy to solve without getting lost in a mess of different units. It is the key to success!
Section 3
Unit multipliers
Because these fractions have units and are equal to 1, we call them unit multipliers. For an equivalent measure like , the two unit multipliers are:
Two unit multipliers for are:
Unit multipliers are like secret identity changers for your numbers! Since they always equal 1, multiplying by them doesn’t change a value, just its name (or unit). You just need to pick the right one to switch from feet to inches, or ounces to pounds. Presto change-o!
Section 4
Converting With Unit Multipliers
When we set up unit conversion problems, we will write the numbers in this order:
Convert 240 yards to feet:
This is a simple matching game! To switch units, pick the unit multiplier that puts the unit you want on top and the unit you are getting rid of on the bottom. The old unit gets canceled out, leaving you with the shiny new unit you wanted. It's a guaranteed win!
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter