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              Example 3:  Find 2436 × 5 by lattice multiplication.                        2       4      3       6

              Solution:    Here, we have to multiply a 4-digit number                   1       2       1      3     5
                             by a 1-digit number, so, we draw a 4 × 1                1     0       0       5    0  0
                             table and proceed as shown alongside.                   0+2=2   0+1=1  5+3=8

                            Thus, 2436 × 5 = 12180.

              Multiplying by a 2-digit Number

              Let us multiply a 2-digit number by a 2-digit number by                             Be Aware
              using lattice multiplication.                                                   We can use the word

              Example 4: Find 74 × 38 by lattice multiplication.                              lattice, instead of
                                                                                              table or grid in lattice
              Solution:  Here, we have to multiply a 2-digit number                           multiplication.
                             by a 2-digit number, so, we draw a 2 × 2 table.

                             Step 1:  Write the numbers in the table as shown.                           7     4

                                                                                                                    3


                                                                                                                    8


                             Step 2:  Draw the diagonals  in  each box  of  the                          7      4
                                      table as shown.                                                               3



                                                                                                                    8


                             Step 3:   Multiply  4  by  3  and  write the  product                        7     4
                                       in  the lattice below 4 as  shown.  Do the                        2  1  1  2  3
                                       same for the product of 7 and 3.
                                                                                                                    8

                             Step 4:   Multiply  4  by  8  and  write the  product                        7     4

                                       in  the lattice below 4 as  shown.  Do the                        2  1  1  2  3
                                       same for the product of 7 and 8.                                  5     3
                                                                                                           6     2  8

                             Step 5:   Add  the  digits  along  the  diagonals  as                        7     4

                                       shown.  The answer  is  read  from left  to                       2  1  1  2  3
                                       right.                                                       2    5     3
                                       The product is 2812.                                        1   =8   1  6  2  8

                                                                                             5+1+1+    1     2
                                       Thus, 74 × 38 = 2812.                                      6+3+2=




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