Definitions:

$$\frac{a}{b}$$ where a is called the numerator and b is called the denominator.

A reduced fraction is a fraction with common terms canceled out of the numerator and denominator.

Multiplication $${\frac{a}{b} * \frac{c}{d}} = {\frac{ac}{bd}}$$ Division $${\frac{a}{b} / \frac{c}{d}} = {\frac{ad}{bc}}$$

A general example to help you recognize patterns and spot the information you're looking for

Multiplication $${\frac{1}{4} * \frac{1}{4}} = {\frac{1 * 1}{4 * 4}} = {\frac{1}{16}}$$ Division $${\frac{2}{4} / \frac{1}{4}} = {\frac{2 * 4}{4 * 1}} = {\frac{8}{4}} = 2$$

We use it when taking measurements of any type.

Multiplying Fractions

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Length: 2:26

Dividing Fractions

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Length: 5:41

Dividing Fractions Word Problem

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Length: 2:08