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    E:\Working\Focus_Learning\Math_Genius_3_(11-09-2024)\Open_Files\CHAP_04
                 \ 12-Sep-2024               Surender Prajapati   Proof-5                     Reader’s Sign _______________________ Date __________

                           Quick Check
                        Complete the following grid for building tables 11 to 20.

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                  Multiplication by 1-Digit nuMber (Without regrouping)

                  Multiplication of a 2-digit number by a 1-digit number

                  We have already learned the multiplication of a 2-digit number by 1 digit. Let us revise.
                  Example: Multiply 12 by 3.

                  Solution:  Step 1: Multiply the ones.  Step 2: Multiply the tens.

                          2 ones × 3 = 6 ones    1 ten × 3 = 3 tens

                                              t O                              t O
                                              1 2                              1 2             Knowledge Desk

                                           ×     3                          ×     3         When multiplying an even
                                                                                            number by 6, the product
                                                  6                            3 6          ends in the same even digit.
                               Thus, 12 × 3 = 36                                            For example, 6 x 2 = 12,
                                                                                            6 x 4 = 24, 6 x 6 = 36, etc.

                  Multiplication of a 3-digit number by a 1-digit  number

                  For preparation of International Mathematics Olympiad (IMO), a teacher gave 3 booklets
                  to each student.
                  Ravi: There are 103 questions in each booklet.

                  Rupa: Okay, then how many questions are there in all the 3 booklets?
                  Ravi: We need to multiply 103 by 3 to know the total number of

                  questions in all.
                  Rupa: Let us arrange the numbers in columns and multiply them step by step.

                  Mathematics-3                                                                                          71

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