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E:\Working\Orange_Education\TouchPad_Maths_4\Open_Files\Chap_03\Chap_03
             \ 10-Nov-2025  Bharat Arora   Proof-8                                     Reader’s Sign _______________________ Date __________





            MulTiPliCATion By 3-DiGiT nuMBErS

            Multiplying by a 3-Digit number Ending with Two 0s


            Let us learn how to multiply a number by a 3-digit number ending with two 0s (100,
            200, 300, ...). Observe the results of the following examples.

              a.  57 × 100 = 5700                                   b.  438 × 100 = 43800
              c.  48 × 200 = (48 × 2) × 100 = 9600                  d.  164 × 300 = (164 × 3) × 100 = 49200

              e.  205 × 400 = (205 × 4) × 100 = 82000  f.  105 × 800 = (105 × 8) × 100 = 84000

            To multiply a number by a 3-digit number ending with two 0s, we write two 0s (00)
            at the end and multiply the number by the digit in the hundreds place.


            Multiplying by any 3-Digit number

            Example 1. Find 276 × 234.

            Solution.

            Step 1.  Multiply by the ones digit.
                       276 × 4 = 1104                                            TTh  Th  H T O

            Step 2.  Multiply by the tens digit.                                         2 7 6
                                                                              ×          2 3 4         200 + 30 + 4
                       276 × 30 = 8280
            Step 3.  Multiply by the hundreds digit.                                 1   1 0 4         276 × 4
                                                                                     8   2 8 0         276 × 30
                       276 × 200 = 55200
                                                                              +   5  5   2 0 0         276 × 200
            Step 4.  Add the products.
                                                                                  6  4   5 8 4         276 × 234
                       1104 + 8280 + 55200 = 64584

            Therefore, 276 × 234 = 64584.


            Example 2. Find 137 × 506.

            Solution.        TTh  Th  H T O                                      TTh  Th  H T O
                                      1 3 7                                               1 3 7

                           ×         5 0 6         500 + 0 + 6                 ×          5 0 6        500 + 0 + 6

                                     8 2 2         137 × 6            Or                  8 2 2        137 × 6
                                     0 0 0         137 × 0                     +  6   8   5 0 0        137 × 500
                           +  6   8  5 0 0         137 × 500                      6   9   3 2 2

                              6   9  3 2 2

            Therefore, 137 × 506 = 69322.




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