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## Arithmetic (all content)

### Course: Arithmetic (all content) > Unit 5

Lesson 21: Multiplying fractions- Intro to multiplying 2 fractions
- Multiplying 2 fractions: fraction model
- Multiplying 2 fractions: number line
- Multiplying fractions with visuals
- Multiplying 2 fractions: 5/6 x 2/3
- Multiplying fractions
- Finding area with fractional sides 1
- Finding area with fractional sides 2
- Area of rectangles with fraction side lengths
- Multiplying fractions review

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# Multiplying fractions review

Review the basics of multiplying fractions, and try some practice problems.

## Multiplying fractions

To multiply fractions, we multiply the numerators and then multiply the denominators.

**Example 1: Fractions**

**Example 2: Mixed numbers**

Before multiplying, we need to write the mixed numbers as improper fractions.

We can also write this as $4{\displaystyle \frac{4}{15}}$ .

*Want to learn more about multiplying fractions? Check out this video.*

### Cross-reducing

Cross-reducing is a way to simplify before we multiply. This can save us from dealing with large numbers in our product.

**Example**

*Prefer a visual understanding of fraction multiplication? Check out one of these videos:*

Multiplying 2 fractions: fraction model

Multiplying 2 fractions: number line

## Practice

*Want to try more problems like this? Check out these exercises:*

Multiply fractions

Multiply mixed numbers

## Want to join the conversation?

- How do you do Cross redusucing?(33 votes)
- Good explanation here : https://www.youtube.com/watch?v=psWT_2QiAVc(4 votes)

- how do you multiply negative

fractions(28 votes)- Multiply the fractions normally, and ensure that the product has the correct sign.

1/2 * 1/2 = 1/4 (Two positives equal a positive.)

-1/2 * -1/2 = 1/4 (Two negatives equal a positive.)

-1/3 * 1/3 = -1/9 (A negative times a positive produces a negative .)

1/3 * -1/3 = -1/9 (The product will be negative, whether the negative number comes first or second.)(22 votes)

- Why do you always have to simplify?(15 votes)
- So the fraction reduced to lowest terms. When we reduce or simplify the fraction, we are writing a fraction in an equivalent form that may be easier to work with.(12 votes)

- What is GCD? thanks to whoever answers it(11 votes)
- greatest common denominator= GCD(1 vote)

- What is the difference between LCD and LCM.(8 votes)
- The mathematical approach to finding the LCM and LCD is the same. For both, we need to find the least common multiple of two or more numbers.
*The least common denominator (LCD) is actually the least common multiple (LCM) of the denominators.*(1 vote)

- How do you multiply the single number with the mixed number?(4 votes)
- You multiply a single number by a mixed number by putting a 1 under the single number.For example 2 + 3 1/2 your new equation would be 2/1 + 3 1/2. This is because 2/1 is the SAME exact thing a 2.(5 votes)

- how do you get the top number on the top like 3 times 2 2/5 how do you get 7 1/5(9 votes)
- In the Multiplying Fractions Review, why is 5/6 x 5/7 clumped together as 5 x 5 with a single line below both and then 6 x 7 also brought together. It seems like an unnecessary step or is there a special meaning to doing this?(5 votes)
- It's just a reminder that when multiplying fractions, we multiply numerator to numerator and denominator to denominator.(13 votes)

- same what's a LCD? can you comment it pls or explan it better.(5 votes)
- If LCD means least common denominator. What does LCM mean?(1 vote)

- I'm realy confused when it comes to math in general.(5 votes)