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E:\Working\Focus_Learning\Math_Genius_3_(11-09-2024)\Open_Files\CHAP_04
             \ 12-Sep-2024               Surender Prajapati   Proof-5                     Reader’s Sign _______________________ Date __________





                           Step 2:  Multiply 42 by 1 ten.                                    H t O

                               42 × 1 ten = 420 ones                                             4 2
                                                                                           ×     1 2
                                Write 420 as the second line product.                            8 4       1st product

                                                                                              4 2 0       2nd product

                           Step 3:  Add the products obtained in step 1 and                  H t O
                                    step 2.                                                      4 2

                              84 + 420 = 504                                              ×      1 2
                                                                                                 8 4       1st product
                                        Thus, 42 × 12 = 504.                              + 4 2 0         2nd product
                                                                                             5 0 4        Sum

              Example 2: Multiply 56 by 32.

              Solution:      Expand the multiplier 32 as 3 tens + 2 ones. Now, follow these steps.
                                     Step 1: Multiply 56  Step 2: Multiply 56 by tens. Step 3: Add the products.
                            by 2 ones.                56 × 3 tens = 56 × 30 ones         112 + 1680 = 1792

                                   56 × 2 ones = 112                      = 1680
                                      Write  112  in  1st  Write 1680 in 2nd product
                             product line.            line.                               th H t O

                            H t O                        th H t O                                5 6
                               5 6                              5 6                     ×        3 2
                                                                                               1 1 2
                         ×     3 2                     ×        3 2                     + 1 6 8 0         1st product
                                1 1 2    1st product          1 1 2       1st product      1 7 9 2        2nd product
                                                                                                          Sum
                                                          1 6 8 0         2nd product

              Thus, 56 × 32 = 1792.

              Multiplication of a 3-digit number by a 2-digit number

              Example 3: Multiply 232 by 23.

              Solution:   Expand the multiplier 23 as 20 + 3 = 2 tens + 3 ones and multiply 232 with it
                             by using the following steps:
                             Step 1:  Multiply 232 by 3 ones.                                          th H t O
                                232 × 3 ones = 696                                                           2 3 2
                                 Write 696 as first line product.                                   ×           2 3

                                                                                                             6 9 6
                             Step 2:  Multiply 232 by 2 tens.                                          th H t O

                                232 × 2 tens = 232 × 20 ones = 4640 ones                                     2 3 2
                                                                                                    ×           2 3
                                 Write 4640 as second line product.                                          6 9 6

                                                                                                        4    6 4 0



              Mathematics-3                                                                                          75
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