The word fraction means a part or a
piece of something. What something? Anything!
The thing could be a gallon of gasoline,
a whole class, a team, a day, anything that you can divide in equal
parts. Once you decide on the parts, you call each one a fraction.
Click on the note to see how it all
works in music and other situations.
 A fraction is just a quick way to tell the
number of parts something has been broken into.
Fractions have two
parts. The top number and the bottom number.
-> This fraction shows that you are talking about 3 parts out of a
total of 4 possible parts.
The bottom number
(the denominator) tells how how many parts make up the whole.
In the figure below, the whole is a octagon (a figure with 8 sides).
If you divide the octagon into four parts, the denominator would be
4.
Four parts make up the whole.
The
top number (the numerator) in a fraction tells how many parts
are selected.
One part is selected. So the fraction is

You will also see fractions written with
a slash instead of a line to separate the numbers.
= 1/4
= 3/4
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