ضرب عدد 37 در مضربهای عدد 3 :                                                                                        

          3 x 37 = 111
          6 x 37 = 222
          9 x 37 = 333
         12 x 37 = 444
         15 x 37 = 555
         18 x 37 = 666
         21 x 37 = 777
         24 x 37 = 888
         27 x 37 = 999
 
                                              این هم جالبه :

  111.111.111   x  111.111.111 = 12.345.678.987.654.321



                      1 x 9 + 2 = 11
                     12 x 9 + 3 = 111
                    123 x 9 + 4 = 1111
                   1234 x 9 + 5 = 11111
                  12345 x 9 + 6 = 111111
                 123456 x 9 + 7 = 1111111
                1234567 x 9 + 8 = 11111111
               12345678 x 9 + 9 = 111111111

دوتا 4 ضلعی دیگه:                                             

                      1 x 8 + 1 = 9
                     12 x 8 + 2 = 98
                    123 x 8 + 3 = 987
                   1234 x 8 + 4 = 9876
                  12345 x 8 + 5 = 98765
                 123456 x 8 + 6 = 987654
                1234567 x 8 + 7 = 9876543
               12345678 x 8 + 8 = 98765432
              123456789 x 8 + 9 = 987654321

        

                      0 x 9 + 8 = 8
                      9 x 9 + 7 = 88
                     98 x 9 + 6 = 888
                    987 x 9 + 5 = 8888
                   9876 x 9 + 4 = 88888
                  98765 x 9 + 3 = 888888
                 987654 x 9 + 2 = 8888888
                9876543 x 9 + 1 = 88888888
               98765432 x 9 + 0 = 888888888
              987654321 x 9 - 1 = 8888888888
             9876543210 x 9 - 2 = 88888888888