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    Step 3. Multiply the hundreds and add the carried over hundreds.                            H    T O
                          2 × 4 = 8 hundreds
                          8 hundreds + 1 hundred = 9 hundreds                                                1   2

                So, 245 × 4 = 980.                                                                          2    4   5
                                                                                                        ×            4

                                                                                                            9    8   0
                            Exercise 4C

                    1.  Find the product.
                        a.        3 0            b.        2 2            c.        1 2 3          d.        2 4 3

                              ×      2                 ×      4                 ×          3              ×         2

                    2.  Find the product.
                        a.       2 6             b.          8 8          c.          9 6 7        d.          6 9 4

                             ×      3                  ×         9              ×             3          ×            4

                    3.  Write the numbers in columns and find the product in your notebook.
                        a.   23 × 3 = _____              b.    16 × 6 = _____              c.   77 × 6 = _____
                        d.   83 × 8 = _____              e.    326 × 3 = _____             f.   436 × 7 = _____

                        g.   784 × 4 = _____             h.    546 × 7 = _____             i.   642 × 5 = _____

                Multiplication by a 2-digit nuMber

                Multiplication of a 2- and 3-digit number by a 2-digit number (Without regrouping)

                example 1. Multiply 42 by 12.
                Solution.  Here, the multiplier  12 = 1 ten + 2 ones = 10 + 2. So, we multiply  42 by  12
                stepwise as shown below.
                Step 1.   Multiply 42 by           Step 2. Multiply 42            Step 3. Add the partial products.
                         the ones.                           by the tens.
                                                                                                 H    T O
                                                                   H   T O                            4   2

                                H    T O                               4    2                ×        1   2
                                                              ×        1    2
                                     4    2                                                           8   4
                            ×        1    2                            8    4                +   4    2   0

                                     8    4                        4   2   0
                                                                                                 5 0      4

                           42 × 2 = 84                       42 × 10 = 420                 84 + 420 = 504
                So, 42 × 12 = 504.

                        78       Mathematics 3

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