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    Exploring Addition

                    We can add numbers in many ways. Let us learn some of them.

                    Expanding numbers

                    Example 1. Add 37 and 22.

                    Solution.
                        Break the numbers into tens                          First add the ones and then the tens.
                        and ones.

                              37               30 + 7                                           37               30 + 7

                         +    22               20 + 2                                       +   22               20 + 2

                                                                              Sum               59               50 + 9

                    Expanding one number

                    Example 2. Find 42 + 16.
                    Solution.

                        Break the smaller number into tens                   Add 42 and 10 first and then add the
                        and ones.                                             sum obtained and 6.

                              42              42                                                42              42

                         +    16              10 + 6                                        +   16              10 + 6

                                                                              Sum               58              52 + 6

                                Exercise 2A

                        1.  Find the sum by expanding the numbers.

                           a.    43 + 84 =                   b.   25 + 36 =                   c.    32 + 24 =

                           d.    34 + 44 =                   e.   56 + 31 =                   f.    45 + 23 =

                       2.  Find the sum by expanding the smaller number.

                           a.    28 + 24 =                   b.   45 + 14 =                   c.    55 + 32 =

                           d.    43 + 21 =                   e.   24 + 15 =                   f.    71 + 26 =

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                                                                                                     Addition

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