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    E:\Working\Brother_Education\Foundational_Stage_Maths-2_(11-09-2024)\Open_Files\Chap_03
                   \ 02-Nov-2023  Bharat Arora   Proof-1                                    Reader’s Sign _______________________ Date __________

                  Estimating Difference

                  To estimate the difference, we round off each number to the nearest tens and then

                  subtract the rounded-off numbers.                                                                                                                                                                 t    O
                                                                                                                                                                                                                    4   12
                  example 2: Estimate the difference between 69 and 24.                                                                                                                                             5    2

                  Solution:  When we estimate the difference between 69 and 24, we subtract the                                                                                                                 –   3    5

                                  tens (70 – 20) and say the difference is about 50.                                                                                                                                1    7
                                        Actual                                     estimated
                                         sum                                           sum
                                       6      9           Rounded up                 7      0

                                  –    2      4           Rounded up           –     2      0

                                       4      5                                      5      0
                                  Actual difference = 45 but estimated difference = 50.

                           Practice Time 3G

                  Find the actual and the estimated sum and difference by rounding off the numbers

                  to the nearest 10. Compare the actual and the estimated sum and difference and

                  fill <, > or = in the given blank space.
                  1.       t   O                     H    t    O      2.      t    O                     H    t   O

                           3   2     round off                                8    7     round off
                       + 6     6     round off    +                        – 2     2     round off    –

                         Actual Sum__________Estimated Sum                 Actual Difference____Estimated Difference

                  SUBTRACTION STORIeS

                  example 1:  Priya has 15 kites and Saransh has 11 kites. Who has more kites and
                                    how many?

                  Solution:         Priya has  15  kites.                         Saransh has  11  kites.

                                    We first compare 15 and 11.

                                    Clearly, 15 > 11, so Priya has more kites.               t    O

                                    Now, we find the difference.                             1    5
                                    15 – 11 = 4 kites                                    –   1    1

                                    So, Priya has 4 more kites than Saransh.                      4

                  64                                                                                     Mathematics-2

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