Page 45 - ICSE Math 5
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Example 2:  Multiply 2,169 by 57.

                    Solution:     2,169 × 57

                                  Multiplicand: 2,169  Multiplier: 57 = 5 tens + 7 ones
                                  Step 1:  Multiply the multiplicand by the digit at the         TTh Th H        T   O
                                            ones place of the multiplier.                              1     4    6
                                                                                                        2   1    6   9
                                            2,169 × 7 ones = 2,169 × 7 = 15,183
                                                                                                  ×                  7


                                                                                                  1     5   1    8   3

                                  Step 2:  Multiply the multiplicand by the digit at the      L TTh Th H         T   O
                                            tens place of the multiplier.                                   3    4
                                                                                                        2   1    6   9
                                            2,169 × 5 tens = 2,169 × 50 = 1,08,450
                                                                                              ×                  5   0

                                                                                              1    0    8   4    5   0

                                  Step 3:  Add the products obtained in Step 1 and Step 2.
                                            15,183 + 1,08,450 = 1,23,633

                                  Alternatively,

                                      L TTh Th H         T    O
                                                     3   4         Carry over of 2,169 × 50
                                                1    4   6         Carry over of 2,169 × 7
                                                2    1   6    9    Multiplicand
                                                                                             So, 2,169 × 57 = 1,23,633.
                                      ×                  5    7    Multiplier
                                                                                             It is read as one lakh
                                           1         1
                                           1    5    1   8    3   (2,169 × 7)              twenty-three thousand six
                                                                                             hundred thirty-three.
                                   + 1     0    8    4   5    0   (2,169 × 50)
                                      1    2    3    6   3    3    Product

                    Example 3:  Multiply 4,396 by 158.

                    Solution:     4,396 × 158
                                                  1    4    3       Carry over of 4,396 × 50
                                                  3    7    4       Carry over of 4,396 × 8
                                                  4    3   9    6   Multiplicand
                                   ×                   1   5    8   Multiplier            So, 4,396 × 158 = 6,94,568.
                                                                                           It is read as six lakh ninety-
                                             2    1
                                            3     5    1   6    8   (4,396 × 8)          four thousand five hundred
                                                                                           sixty-eight.
                                       2    1     9    8   0    0    (4,396 × 50)
                                   +   4    3     9    6   0    0    (4,396 × 100)

                                       6    9     4    5   6    8   Product

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