## Multiplying and Dividing Mixed Numbers

### Learning Outcomes

• Multiply mixed numbers and fractions
• Divide an integer by a fraction
• Divide a mixed number by an integer

In the previous module’s review section, you learned how to multiply and divide fractions. All of the examples there used either proper or improper fractions. What happens when you are asked to multiply or divide mixed numbers? Remember that we can convert a mixed number to an improper fraction. And you learned how to do that in Visualize Fractions.

### Example

Multiply: $3\Large\frac{1}{3}\cdot \frac{5}{8}$

Solution:

 $3\Large\frac{1}{3}\cdot \frac{5}{8}$ Convert $\Large3\frac{1}{3}$ to an improper fraction. $\Large\frac{10}{3}\cdot \frac{5}{8}$ Multiply. $\Large\frac{10\cdot 5}{3\cdot 8}$ Look for common factors. $\Large\frac{\color{red}{2}\cdot 5\cdot 5}{3\cdot \color{red}{2} \cdot 4}$ Remove common factors. $\Large\frac{5\cdot 5}{3\cdot 4}$ Simplify. $\Large\frac{25}{12}$

Notice that we left the answer as an improper fraction, $\Large\frac{25}{12}$, and did not convert it to a mixed number. In algebra, it is preferable to write answers as improper fractions instead of mixed numbers. This avoids any possible confusion between $2\Large\frac{1}{12}$ and $2\cdot\Large\frac{1}{12}$ (which are not equal!).

### Try it

Watch the following video for another example of how to multiply a mixed number by a fraction.

### Multiply or divide mixed numbers

1. Convert the mixed numbers to improper fractions.
2. Follow the rules for fraction multiplication or division.
3. Simplify if possible.

### Example

Multiply, and write your answer in simplified form: $2\Large\frac{4}{5}\left(\normalsize -1\Large\frac{7}{8}\right)$

### Try It

In the following video we show more examples of how to multiply mixed numbers that are negative.

### Example

Divide, and write your answer in simplified form: $3\Large\frac{4}{7}\normalsize\div 5$

### Example

Divide: $2\Large\frac{1}{2}\normalsize\div 1\Large\frac{1}{4}$

### Try It

The next video provides several more examples of dividing mixed numbers, whole numbers and fractions.