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    exploriNg MulTipliCATioN

                    Multiplying by expanding the Bigger Number

                    example 1. Multiply: 67 × 5                          example 2. Multiply: 143 × 3
                    Solution.                                            Solution.

                    Step 1.  67 × 5 = ?       67                         Step 1.  143 × 3 = ?                    143

                                          60  +  7                                                        100  +  40  +  3
                    Step 2.  60 × 5 =   300                              Step 2. 100 × 3 =   300

                                  7 × 5 = +  35                                     40 × 3 =   120
                                           335                                      3 × 3 = +      9

                                                                                                 429

                    So, 67 × 5 = 335.                                    So, 143 × 3 = 429.

                    Multiplying by 1
                    observe the following:

                           a.  7 × 1 = 7                   b.  53 × 1 = 53                 c.  124 × 1 = 124
                    When a number is multiplied by 1, the product is the number itself.

                    Multiplying by Zero
                    observe the following:

                           a.  5 × 0 = 0                   b.  17 × 0 = 0                  c.  124 × 0 = 0
                    When a number is multiplied by zero, the product is always zero.

                    Multiplying by 10
                    Look at the following multiplications.

                           a.  3 × 10 = 30                 b.  12 × 10 = 120               c.  324 × 10 = 3240
                    To multiply a number by 10, write a ‘0’ to the right of the number.

                    Multiplying by Tens other than 10

                    Observe the following multiplications.
                           a.  12 × 20 = 240               b.  36 × 30 = 1080              c.  26 × 60 = 1560

                    To multiply a number by 20, 30, 40, ..., 90, first multiply the numbers without zero.
                    Then add a zero (0) to the right of the product obtained.
                    Multiplying by 100

                    Let us see how to multiply a number by 100.

                           a.  1 × 100 = 100               b.  5 × 100 = 500               c.  17 × 100 = 1700
                    To multiply a number by 100, write two zeros (00) to the right of the number.

                                                                                                                  81
                                                                                                 Multiplication

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