Page 210 - Basic College Mathematics with Early Integers
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S E C T I O N  3.2 I FACTORS AND SIMPLEST FORM                  187

            The method for simplifying negative fractions is the same as for positive fractions.


                                                   10
             Example 6      Write in simplest form:  -                                  PRACTICE 6
                                                   27
                                                                                                                9
             Solution:                                                                  Write in simplest form:  -
                                                                                                                50
                            #
                   10      2 5
                 -    =-         Prime factorizations of 10 and 27
                           # #
                   27    3 3 3
                                                   10
             Since 10 and 27 have no common factors, -  is already in simplest form.
                                                   27
              Work Practice 6


                                                  30
             Example 7      Write in simplest form:                                     PRACTICE 7
                                                  108
                                                                                                               49
             Solution:                                                                  Write in simplest form:  112
                           # #
                 30      2 3 5       2 3    5           5    5
                                                    # #
                     =            =   # #       = 1 1     =
                         # # # #
                                           # #
                 108   2 2 3 3 3     2 3 2 3 3         18   18
              Work Practice 7
                We can use a shortcut procedure with common factors when simplifying.
                       1
                             #
                      #
                4    2  2  1 2    2  Divide out the common factor of 2 in the
                  =      =      =
                             #
                      #
                6    2  3  1 3    3  numerator and denominator.
                       1
            This procedure is possible because dividing out a common factor in the numerator
            and denominator is the same as removing a factor of 1 in the product.
              Writing a Fraction in Simplest Form

              To write a fraction in simplest form,write the prime factorization of the numerator
              and the denominator and then divide both by all common factors.



                                                   72
             Example 8      Write in simplest form:  -                                  PRACTICE 8
                                                   26
                                                                                                                64
             Solution:                                                                  Write in simplest form:  -  20
                            1
                                           # # # #
                            # # # #
                   72     2  2 2 3 3      1 2 2 3 3      36
                 -    =-              =-             =-
                               #
                                              #
                   26        2  13           1 13        13
                               1
              Work Practice 8
                                                                           15
              Concept Check Which is the correct way to simplify the fraction    ?
                                                                           25
              Or are both correct? Explain.
                         1                   1                                          Answers
                      #
               15   3  5     3           1  5    11
            a.    =       =           b.      =                                             9    7      16
                     #
               25   5  5     5           2  5    21                                     6. -   50  7.  16  8. -  5
                         1                   1
                                                                                          Concept Check Answers
                                                                                        a. correct b. incorrect
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