1. A Fraction Can Be Used to Indicate Equal Parts of a Whole. In our everyday lives, we often deal with parts of a whole. For example, we talk about parts of an
hour, parts of an inch, and parts of a pound.
half of an hour
three-eighths of an inch of rain
a quarter-pound hamburger
2. A Fraction Is Composed of a Numerator, a Denominator,
and a Fraction Bar.
Fraction bar ¡
3 — Numerator
4 — Denominator
The denominator (in this case, 4) tells us that a whole was divided into four equal
parts. The numerator tells us that we are considering three of those equal parts.
3. Fractions Can Be Proper or Improper. If the numerator of a fraction is less
than its denominator, the fraction is called a proper fraction. A proper fraction is less
than 1. Fractions whose numerators are greater than or equal to their denominators
are called improper fractions.
Proper fractions
Improper fractions
1
,
4
7
,
2
2
, and
3
98
99
98
,
97
16
, and
16
5
1
4. The Denominator of a Fraction Cannot Be 0. 70, 230, and
7 23
0, 0 ,
expressions. (Recall that
divided by 0.) However, 07 0
and 00 represent
0
and 23
0.
0
0
are meaningless
division by 0, and a number cannot be
5. Fractions Can Be Negative. There are times when a negative fraction is needed
to describe a quantity. For example, if an earthquake causes a road to sink one-half
inch, the amount of movement can be represented by 12 inch.
Negative fractions can be written in three ways. The negative sign can appear in
the numerator, in the denominator, or in front of the fraction.
1
1
1
2
2
2
15
15
15
8
8
8
Negative fractions
If a and b represent positive numbers,
a
a
a
b
b
b