Learning Outcomes
- Translate phrases into algebraic expressions that involve division
- Identify a complex fraction
- Simplify complex fractions
Translate Phrases to Expressions with Fractions
The words quotient and ratio are often used to describe fractions. In Subtract Whole Numbers, we defined quotient as the result of division. The quotient of [latex]a\text{ and }b[/latex] is the result you get from dividing [latex]a\text{ by }b[/latex], or [latex]\Large\frac{a}{b}[/latex]. Let’s practice translating some phrases into algebraic expressions using these terms.
Example
Translate the phrase into an algebraic expression: “the quotient of [latex]3x[/latex] and [latex]8[/latex].”
Solution:
The keyword is quotient; it tells us that the operation is division. Look for the words of and and to find the numbers to divide.
[latex]\text{The quotient }\text{of }3x\text{ and }8\text{.}[/latex]
This tells us that we need to divide [latex]3x[/latex] by [latex]8[/latex].
[latex]\Large\frac{3x}{8}[/latex]
try it
Example
Translate the phrase into an algebraic expression: the quotient of the difference of [latex]m[/latex] and [latex]n[/latex], and [latex]p[/latex].
Try it
In the following video we show more examples of translating English expressions into algebraic expressions.
Simplify Complex Fractions
Our work with fractions so far has included proper fractions, improper fractions, and mixed numbers. Another kind of fraction is called complex fraction, which is a fraction in which the numerator or the denominator contains a fraction.
Some examples of complex fractions are:
[latex]\LARGE\frac{\frac{6}{7}}{ 3}, \frac{\frac{3}{4}}{\frac{5}{8}}, \frac{\frac{x}{2}}{\frac{5}{6}}[/latex]
To simplify a complex fraction, remember that the fraction bar means division. So the complex fraction [latex]\LARGE\frac{\frac{3}{4}}{\frac{5}{8}}[/latex] can be written as [latex]\Large\frac{3}{4}\normalsize\div\Large\frac{5}{8}[/latex].
Example
Simplify: [latex]\LARGE\frac{\frac{3}{4}}{\frac{5}{8}}[/latex]
Try it
The following video shows another example of how to simplify a complex fraction.
Simplify a complex fraction.
- Rewrite the complex fraction as a division problem.
- Follow the rules for dividing fractions.
- Simplify if possible.
Example
Simplify: [latex]\LARGE\frac{-\frac{6}{7}}{ 3}[/latex]
Try it
Example
Simplify: [latex]\LARGE\frac{\frac{x}{2}}{\frac{xy}{6}}[/latex]
Try it
Example
Simplify: [latex]\LARGE\frac{2\frac{3}{4}}{\frac{1}{8}}[/latex]
