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E:\Working\Focus_Learning\Math_Genius_3_(11-09-2024)\Open_Files\CHAP_03
             \ 12-Sep-2024  Surender Prajapati   Proof-5                                  Reader’s Sign _______________________ Date __________





              addition and Subtraction together

              Navya had `2666 in her bank account. She withdrew `1095 in the first month, `996 in
              the second month and the rest in the third month. How much money did she withdraw

              in the third month?
              To know the amount she withdrew in the third month, first we add `1095 and `996, then

              subtract the sum obtained from `2666.
              Step 1: Add 1095 and 996                                                                   th H t O
                                                                                                         1   1   1
                       Amount of money she withdrew in the first month                            = `    1   0 9 5

                       Amount of money she withdrew in the second month                           = + `      9 9 6
                       Amount of money she withdrew in the two months                             = ` 2      0 9 1
              Step 2: Now, subtract `2091 from `2666.                                                    th H t O

                                                                                                             5 16
                       Amount of money she had in her bank account                                = ` 2      6 6    6
                       Amount of money she withdrew in the first two months                       = – ` 2    0 9 1
                       Amount of money she withdrew in the third month                            = ` 0      5 7 5

                 Thus, she withdrew `575 in the third month.

              Example 1: Solve 4578 – 3795 + 2563 – 1789

              Solution:   Firstly, subtract 3795 from 4578. Then add 2563 to the difference obtained
                             and subtract 1789 from the sum to get the answer.

                                                                                              th H      t   O
                                th H     t    O                th H      t   O                     12   13
                                3   14   17                     1   1                          2    2   3   16
                                4    5   7    8                     7    8   3                 3   3    4    6
                             – 3     7   9    5             + 2     5    6   3              – 1    7    8    9
                                0    7   8    3                 3   3    4   6                 1   5    5    7

              Alternative Method: We can also solve it by using given steps:

              Step 1:  Add the numbers  Step 2:  Add the numbers              Step 3:  Subtract the sum obtained
                       having (+) signs              having (–) sign.                 in step 2 from the sum

                      th H     t    O                th H      t   O                  obtained in step 1.
                      1    1   1                      1   1    1                           th H      t   O
                      4    5   7    8                 3   7    9   5                            10  13
                   + 2     5   6    3             + 1     7    8   9                        6   11  14   11
                      7    1   4    1                 5   5    8   4                        7   1    4   1
                                                                                        – 5     5    8   4
                                                                                            1   5    5   7
                             Thus, 4578 – 3795 + 2563 – 1789 = 1557.



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