4.4+Multiplying+Fractions

Section 4.4 Multiplying Fractions
Multiplying is the easiest of operations when it comes to fractions.

__To multiply two fractions__: 1) Place the fractions side by side. 2) Multiply the numerators. 3) Multiply the denominators. 4) Reduce, if possible.


 * Super Secret Time Saving Trick**

It's so secret that I don't dare write it down. But if you ask me about reducing before multiplying fractions, I'll show you. And if someone else writes it here, well, that would be fine.


 * "Of" means times!**

At least it does most of the time in math.

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 * Multiplication with Mixed Numbers**

//Don't do it.// Convert the mixed numbers to improper fractions and then multiply. Convert the answer back to a mixed number, if needed.


 * Application of Multiplication with Fractions**

You would do any problems that require multiplication the same way with fractions as you would with whole numbers.

__Problem 1__: Find the area of the rectangle.

__Problem 2__: Three eighths (3/8) of all students who visit Scoops in the Student Center during the summer buy ice cream. If 440 people come in in one day, how many would you expect to buy ice cream? (We will revisit problems like this in a later chapter on proportions.)

__Problem 3__: The formula for area of a triangle is one half times the base times the height. Base can be understood much like the length is on a rectangle, but height is not always the same as width. The height is the distance from the base to the highest part of the triangle if it were "sitting on it's base".

Look at these two triangles. Can you see that the area of a triangle is half of a rectangle? Even though other triangles don't always have square corners, the same formula for area applies.



What is the area of the green triangle below?

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 * Chapter Four Practice Problems**

**Where to from here?**
4.1 Greatest Common Factor 4.2 What is a Fraction? 4.3 Equivalent Fractions 4.4 Multiplying Fractions 4.5 Dividing Fractions 4.6 Adding and Subtracting Like Fractions 4.7 Adding and Subtracting Unlike Fractions 4.8 Fraction Coefficients 4.9 Solving for X with Fractions Chapter Four Review Chapter Four Homework