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               \ 08-Oct-2025  Bharat Arora   Proof-9                                 Reader’s Sign _______________________ Date __________





          Among the 8-digit numbers:   C tL L TTh Th H t O  Example 1:  Form the smallest number using the following digits:

          27504545 < 51889620 < 53072249 <  86121450.  5 3 0  7  2 2 4 9  8-digit     (  a)  4, 5, 6, 8, 3, 7        (b)  2, 5, 3, 0, 1, 9
 5 1 8  8  9 6 2 0  8-digit
          So, the ascending order of the numbers is:  8 6 1  2  1 4 5 0  8-digit  Solution:   (a)  The smallest digit is 3.

          983250 < 27504545 < 51889620 < 53072249  2 7 5  0  4 5 4 5  8-digit              The other digits in ascending order are 4, 5, 6, 7 and 8.
 < 86121450  9  8  3 2 5 0  6-digit              So, the smallest number formed by the given digits is 345678.
                            (  b)  The smallest digit is 1 (other than 0).                         Be Aware
 Example 5:  Arrange the following numbers in descending order:
                                   The  other  digits in  ascending  order  are  0,  2,  3,  5   0 at the leftmost
          83672906, 74635618, 83910257, 9876879, 74613898  and 9.                              place has no meaning.

 Solution:   Let us arrange the given numbers in the place value chart.                So, the smallest number formed by the given digits is 102359.
          Clearly, 83672906 and 83910257, both have   C tL L TTh Th H t O  To form the greatest number using the given digits, write the greatest digit at the leftmost
 the  same  digits  in  the  two  leftmost  places,   8 3 6  7  2 9 0 6  8-digit  place and then write the other digits in their descending order.

 i.e., 8 and 3, and the digits in the next place   7 4 6  3  5 6 1 8  8-digit  Example 2: Form the greatest number using the following digits:
 from the left (lakhs place) are 6 and 9.  8 3 9  1  0 2 5 7  8-digit           (  a)  8, 5, 9, 6, 3, 2         (b)  4, 0, 3, 5, 6, 7
 9 8  7  6 8 7 9  7-digit
          9 > 6  7 4 6  1  3 8 9 8  8-digit  Solution:    (  a)  Here, the greatest digit among the given digits is 9.

          So, 83910257 > 83672906.              The other digits in descending order are 8, 6, 5, 3 and 2.
                                 So, the greatest number formed by the given digits is 986532.
          Now, 74635618 and 74613898, both have the same digits in the three leftmost            (  b)  Here, the greatest digit among the given digits is 7.

 places,  i.e.,  7,  4  and  6,  and  the  digits  in  the  next  place  from  the  left  (ten
 thousands place) are 3 and 1.              The other digits in descending order are 6, 5, 4, 3 and 0.
                                 So, the greatest number formed by the given digits is 765430.
          3 > 1  with repetition of Digits
          So, 74635618 > 74613898.
              To form the smallest number, we repeat the smallest digit.
          9876879 is a 7-digit number. Hence, it is the smallest number.
              Example 3:  Form the smallest 8-digit number using the digits 2, 3, 1, 4, 5 and 0.
          So, the given numbers in descending order are:  Solution:   To form the smallest 8-digit number using the given digits, repeat the smallest

          83910257 > 83672906 > 74635618 > 74613898 > 9876879  digit 0 thrice. Thus, the smallest 8-digit number formed using the given digits
                            is 10002345.
 Think Tank  Critical Thinking  To form the greatest number, we repeat the greatest digit.

 Write your mother's and father's date of birth in the form of ddmmyyyy and   Example 4:  Form the greatest 7-digit number using the digits 5, 1, 4, 3 and 2.
 compare both the numbers thus formed.
              Solution:     To form the greatest 7-digit number using the given digits, repeat the greatest
                            digit 5 thrice. Thus, the greatest 7-digit number formed using the given digits
 Forming numbers            is 5554321.

 without repetition of Digits  Practice time 1c

 Many  numbers  can  be  formed  with  given  digits.  We  know  the  method  of  forming  the

 smallest and the greatest numbers using given digits.    1.  Fill in the blanks using <, > or = .
                    (  a)  805637      707656                        (b)  2056953         206075
 To form the smallest number using the given digits, write the smallest digit other than zero
 (0) at the leftmost place and then write zero (0) if given, otherwise write the other digits      (  c)  8670757    8670954   (d)  44524017    44324017
 in their ascending order.     (  e)  42003600    42003600           (f)  79000000         79999999


              Mathematics-5                                                                                          1717
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