In this Grade 6 lesson from Big Ideas Math Advanced 1, students learn to solve proportions using the Multiplication Property of Equality and the Cross Products Property. The lesson covers setting up and solving proportions with variables, applied through real-world contexts such as calculating dissolved compounds in solutions and converting units using ratios. Students practice both algebraic methods across a range of proportion problems, including those with variable expressions in the denominator.
Section 1
Multiplication Property of Equality for Proportions
Multiplication Property of Equality: Multiplying both sides of an equation by the same non-zero number maintains the equality. If and , then . This property is essential for solving proportions by isolating the variable.
Section 2
Solving Proportions Using Cross Products
To solve a proportion , use the cross products property: . Then solve the resulting equation using basic algebraic operations.
Section 3
Basic Unit Conversions Using Proportions
Use proportions to convert between different units of measurement. Set up a proportion where one ratio contains the given measurement and unknown converted value, and the other ratio contains the conversion factor. Cross multiply to solve for the unknown value.
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Section 1
Multiplication Property of Equality for Proportions
Multiplication Property of Equality: Multiplying both sides of an equation by the same non-zero number maintains the equality. If and , then . This property is essential for solving proportions by isolating the variable.
Section 2
Solving Proportions Using Cross Products
To solve a proportion , use the cross products property: . Then solve the resulting equation using basic algebraic operations.
Section 3
Basic Unit Conversions Using Proportions
Use proportions to convert between different units of measurement. Set up a proportion where one ratio contains the given measurement and unknown converted value, and the other ratio contains the conversion factor. Cross multiply to solve for the unknown value.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter