Basic Mathematics for College Students

(Nandana) #1
Chapter 3 Summary and Review 309

A complex fraction is a fraction whose
numerator or denominator, or both, contain
one or more fractions or mixed numbers.


Complex fractions:

 7

1


4


2 


1


9


2


5





1


3


3


7





1


5


9


10


27


5


The method for simplifying complex fractions
is based on the fact that the main fraction bar
indicates division.


Simplify:

Use the rule for dividing fractions: Multiply the
first fraction by the reciprocal of , which is.

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

1


6


To simplify, factor 10 as 25 and 27 as 39.
Then remove the common factors of 9 and 5
from the numerator and denominator.




9


1
 5

1

2  5
1

 3  9


1

Multiply the numerators.
 Multiply the denominators.

9  5


10  27


5
27

27
5




9


10





5


27


Write the division indicated by the
main fraction bar using a symbol.

9


10


27


5





9


10





27


5


9


10


27


5


To simplify a complex fraction:



  1. Add or subtract in the numerator and/or
    denominator so that the numerator is a
    single fraction and the denominator is a
    single fraction.

  2. Perform the indicated division by
    multiplying the numerator of the complex
    fraction by the reciprocal of the
    denominator.

  3. Simplify the result, if possible.


Simplify:

Use the rule for dividing fractions:
Multiply the first fraction by the
reciprocal of , which is.

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




7


66


To simplify, factor 35 as 57 and 15 as 35.
Then remove the common factor of 5 from
the numerator and denominator.




1  5


1
 7
3  5
1

 22


Multiply the numerators.
 Multiply the denominators.

1  35


15  22


35
22

22
35




1


15





35


22


Write the division indicated by the main
 fraction bar using a symbol.

1


15





22


35


Subtract the numerators and write the
difference over the common denominator 15.
Add the numerators and write the sum
over the common denominator 35.




1


15


22


35


Multiply the numerators.
 Multiply the denominators.

6


15





5


15


15


35





7


35


In the numerator, build each fraction so
that each has a denominator of 15.
In the denominator, build each fraction so
that each has a denominator of 35.

2


5





1


3


3


7





1


5





2


5





3


3





1


3





5


5


3


7





5


5





1


5





7


7


2


5





1


3


3


7





1


5

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