Question 38610
<pre><font size = 4><b>Express the following compound fraction in lowest terms: 


                     9r<sup>2</sup>s
                    ——————
                     7pq<sup>2</sup>
                  —————————
                    3r<sup>3</sup>s<sup>3</sup>
                   ———————
                     14q<sup>5</sup>

Write as a division problem:

                     9r<sup>2</sup>s     3r<sup>3</sup>s<sup>3</sup>
                    —————— ÷ ———————
                     7pq<sup>2</sup>      14q<sup>5</sup>
                
Then we invert the second franction and change
the division to multiplication:


                     9r<sup>2</sup>s      14q<sup>5</sup>
                    —————— × ———————
                     7pq<sup>2</sup>     3r<sup>3</sup>s<sup>3</sup>
             
Multiply the tops and bottoms:


                      9·14r<sup>2</sup>sq<sup>5</sup>
                    ————————————
                     7·3pq<sup>2</sup>r<sup>3</sup>s<sup>3</sup>

Cancel the 7 into the 14 and the 3 into the 9

                      3  2
                      <s>9</s>·<s>14</s>r<sup>2</sup>sq<sup>5</sup>
                    ————————————
                     <s>7</s>·<s>3</s>pq<sup>2</sup>r<sup>3</sup>s<sup>3</sup>
                     1 1

or

                       6r<sup>2</sup>sq<sup>5</sup>
                     —————————
                      pq<sup>2</sup>r<sup>3</sup>s<sup>3</sup>

Give both the s on top and the p on the bottom exponents of 1

                       6r<sup>2</sup>s<sup>1</sup>q<sup>5</sup>
                     —————————
                      p<sup>1</sup>q<sup>2</sup>r<sup>3</sup>s<sup>3</sup>

Use this rule of division of exponentials with like bases:

Subtract exponents LARGER MINUS SMALLER, and place the result
in the numerator or denominator, depending of which contains
the larger exponent:

For the r's, the larger exponent is 3, of r<sup>3</sup>, and it is in the
bottom so we subtract the exponents 3-2, getting 1 and we place
r<sup>1</sup> in the bottom and eliminate r from the top

                       6s<sup>1</sup>q<sup>5</sup>
                     ——————————
                      p<sup>1</sup>q<sup>2</sup>r<sup>1</sup>s<sup>3</sup>

For the s's, the larger exponent is 3, of s<sup>3</sup>, and it is in the
bottom so we subtract the exponents 3-1, getting 2 and we place
s<sup>2</sup> in the bottom and eliminate s from the top:

                        6q<sup>5</sup>
                     ——————————
                      p<sup>1</sup>q<sup>2</sup>r<sup>1</sup>s<sup>2</sup>

For the q's, the larger exponent is 5, of q<sup>5</sup>, and it is in the
top so we subtract the exponents 5-2, getting 3 and we place
q<sup>3</sup> in the top and eliminate q from the bottom:

                        6q<sup>3</sup>
                     ————————
                      p<sup>1</sup>r<sup>1</sup>s<sup>2</sup>

Now we erase the 1 exponents on the p and r in the bottom:

                        6q<sup>3</sup>
                      ——————
                       prs<sup>2</sup>

Edwin
AnlytcPhil@aol.com</pre>