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    example 2. Multiply 210 by 4.
                    Solution.
                    Step 1. Multiply the ones.         Step 2. Multiply the tens.        Step 3. Multiply the hundreds.

                                H    T O                           H    T O                             H    T O

                                2    1   0                         2    1   0                           2    1   0

                           ×             4                     ×            4                      ×             4

                                         0                              4   0                           8   4    0

                           0 × 4 = 0 ones                      1 × 4 = 4 tens                   2 × 4 = 8 hundreds

                    So, 210 × 4 = 840.
                    Multiplication of a 2- and 3-digit Number by a 1-digit Number (With regrouping)

                    example 3. Multiply 25 by 3.
                    Solution.

                    Step 1. Multiply the ones and regroup.  Step 2. Multiply the tens and add the
                                                                               carried over tens.
                                    T O                                              T O

                                    1                                                 1

                                    2   5                                            2    5
                               ×        3                                        ×        3

                                        5                                            7    5

                    5 × 3 = 15 ones = 1 ten 5 ones                    2 × 3 = 6 tens and 6 tens + 1 ten = 7 tens
                    So, 25 × 3 = 75.

                    example 4. Multiply 245 by 4.
                    Solution.
                    Step 1. Multiply the ones and regroup.  Step 2.  Multiply the tens, add the carried

                                                                               over tens and regroup.

                                   H    T O                                          H    T O
                                        2                                             1   2

                                   2    4   5                                        2    4   5

                               ×            4                                    ×            4

                                            0                                             8   0

                    5 × 4 = 20 ones = 2 tens 0 ones                   4 × 4 = 16 tens
                                                                      16 tens + 2 tens = 18 tens = 1 hundred 8 tens

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                                                                                                 Multiplication

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