Basic Mathematics for College Students

(Nandana) #1
Chapter 3 Summary and Review 297

There are four special fraction forms that
involve 0 and 1.
Each of these fractions is a form of 1:

1  ...
1
1

2
2

3
3

4
4

5
5

6
6

7
7

8
8

9
9


Simplify each fraction:

is undefined

20


20


 1


5


1


 5


7


0


0


8


 0


Two fractions are equivalentif they represent
the same number. Equivalent fractions
represent the same portion of a whole.

, , and are equivalent fractions. They represent the same shaded
portion of the figure.

(^2) –
3 =
(^4) –
6 =
––^8
12
8
12
4
6
2
3
To build a fraction,we multiply it by a factor of
1 in the form 22 ,^33 ,^44 ,^55 ,and so on.
Write as an equivalent fraction with a denominator of 36.
1
We must multiply the denominator of by 9 to obtain a
denominator of 36. It follows that should be the form
of 1 that is used to build.
(^2736) is equivalent to. (^34)





27


36


Multiply the numerators.
 Multiply the denominators.

3  9


4  9


3
4

9
9

3
3 4
4




3


4





9


9


3
4

A fraction is in simplest form,or lowest terms,
when the numerator and denominator have no
common factors other than 1.

Is in simplest form?
The factors of the numerator, 6, are: 1 , 2 ,3,6.
The factors of the denominator, 14, are: 1 , 2 ,7,14.
Since the numerator and denominator have a common factor of 2, the
fraction is 146 notin simplest form.

6
14

To simplify a fraction,we write it in simplest
form by removing a factor equal to 1:


  1. Factor (or prime factor) the numerator
    and denominator to determine their
    common factors.

  2. Remove factors equal to 1 by replacing
    each pair of factors common to the
    numerator and denominator with the
    equivalent fraction.

  3. Multiply the remaining factors in the
    numerator and in the denominator.


1
1

Simplify:

Prime factor 12 and 30.

Since 2 and 5 have no common factors other than 1, we say that is in
simplest form.

2
5

Multiply the remaining factors in the numerator:
1  2  1 2.
Multiply the remaining factors in the denominator:
1  1  5 5.




2


5


Remove the common factors of 2 and 3
 from the numerator and denominator.

2


1
 2  3

1

2
1

 3


1

 5


12


30





2  2  3


2  3  5


12


30


If the numerator of a fraction is less than its
denominator, the fraction is called a proper
fraction.If the numerator of a fraction is
greater than or equal to its denominator, the
fraction is called an improper fraction.


Proper fractions: and Proper fractions are less than 1.

Improper fractions: and

Improper fractions are greater
than or equal to 1.

15


15


3


2


,


41


16


,


999


1,000


1


5


,


7


8


,

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