Page 29 - ArithBook5thEd ~ BCC
P. 29

√
               The side length of the middle square is a number which, when squared, yields 5, that is,  5. We can
                       √                √                    √
               see that  5is bigger than  4= 2, and less than  9= 3.
                   In general, if a whole number lies between two perfect squares, its square root must lie between the
               two corresponding square roots.
                                                                             √                   √
               Example 21. Since 21 lies between the perfect squares 16 and 25,  21 must lie between  16 = 4 and
               √
                 25 = 5.
                                                                             √
               Example 22. Between what two consecutive whole numbers does    53 lie?

                                                                                         √
               Solution. Since 53 lies between the perfect squares 49 and 64, the square root  53 must lie between
               √            √
                 49 = 7 and   64 = 8.

               1.4.4   Exercises

               Find the square roots:
                   √
                1.   49
                   √
                2.   81
                   √
                3.   169
                   √
                4.   121

                   √
                5.   64
               Between what two consecutive whole numbers do the following square roots lie?

                   √
                6.   19
                   √
                7.   75
                   √
                8.   26
                   √
                9.   32

               10. Complete the square-root table:
                    √
                      0=                          =6                  =12                 =18
                    √
                      1=                          =7                  =13                 =19
                    √
                      4=                          =8                  =14                 =20
                    √
                      9=                          =9                  =15                 =30
                               =4                 =10                 =16                 =40
                               =5                 =11                 =17                 =50


               1.5     Division of Whole Numbers


               How many times does 23 “go into” 100? Put another way, starting with 100, how many times can we
               subtract 23 without obtaining a negative number? The answer is easily seen to be 4. Moreover, it is



                                                           Page 29
   24   25   26   27   28   29   30   31   32   33   34