Basic HTML Version

|  | Table of Contents |  | View Full Version

Page 63 - Math Genius C2
P. 63

    E:\Working\Orange_Education\Math_Genius_2\Open_Files\Chap_03
                   \ 26-Sep-2025  Bharat Arora   Proof-10                                   Reader’s Sign _______________________ Date __________

                  5.     t    O                t   O                      6.      t   O                t    O

                         5    1                                                   5    6
                     –   2    7            +                                  –   3    8           +

                  RelATION BeTWeeN ADDITION AND SUBTRACTION

                  There is a special relationship between addition and subtraction facts. This

                  relationship can be seen in fact families. A fact family is a set of facts with the same
                  three numbers. Look at the collection of stars.

                  In the following fact family, all four facts have the numbers 6, 9 and 15.

                        t   O             t   O             t   O             t   O

                             6                 9            1    5            1    5
                    +        9        +        6        –        9        –        6
                        1    5            1    5                 6                 9

                  There are 18 caps. Out of these, 12 are green and 6 are red.

                                                                                              Knowledge Desk

                                                                                            Did you know that a
                  Let us write the fact family for 6, 12 and 18.                            woman's heart generally

                       t   O             t   O             t   O             t   O          beats faster than a man’s?

                       1    2                 6            1    8            1    8         A woman's heart beats 82
                                                                                            times per minute, while a
                   +        6        +   1    2        –   1    2        –        6         man's beats 78 times.
                       1    8            1    8                 6            1    2

                           Practice Time 3e

                  Write the fact family for each group of numbers.

                    1.         5, 6, 11                 2.        9, 12, 21               3.        17, 21, 38

                               +       =                          +        =                         +       =

                               +       =                          +        =                         +       =

                               –       =                          –        =                         –       =

                               –       =                          –        =                         –       =

                  Mathematics-2                                                                                          61

| 58 59 60 61 62 63 64 65 66 67 68 |