INTRODUCTION TO FRACTIONS
Fractions are expressed as one number over another number, like this:
The number on the top is called the numerator and the number on the bottom is called the denominator.
When you think of a fraction, think of a PIZZA!!
Suppose a pizza is cut evenly into the number of pieces in the DENOMINATOR. If the number of pieces YOU get is the NUMERATOR, the fraction of the pizza you get is:
Adding and taking away (subtracting) fractions can be pictured using slices of pizza. For example:
Multiplying fractions means cutting a portion into smaller portions.
Unit 1 show you how to do this multiplication.
Dividing fractions means determining how many smaller pieces there are in a larger piece. For example:
This means there are 2 one-fourth pieces of pizza in a half pizza.
Unit 4 shows you how to do this division.
Unit 12 will introduce you to decimals.
Here's another way to look at fractions. Imagine that each of these lines is a board and you want to cut it into halves, thirds, fourths, sixths, and fifths. Here is what those board fractions look like:
| 1/4 board || 1/4 board
|| 1/4 board || 1/4 board |
|1/3 board||1/3 board
|1/6 board||1/6 board||1/6 board
||1/6 board||1/6 board||1/6 board|
|1/5 board||1/5 board||1/5 board||1/5 board
Notice that the 2 1/4th boards add up to a half board and that the 2 1/6 boards add up to a 1/3 board.
This means that 2/4=1/2 and 2/6=1/3. (We will investigate this more in unit 9.)
So now, let's begin our drills!