Answers

2016-06-06T15:54:02+08:00
First multiply the one digit number with the ones of the two digit number
For ex:   42
            x  3
          ---------   Multiply the 3 with 2 then you got 6.
                6
     
Then multiply the one digit number with the tens of the two digit number.

     42
 x    3
---------- 
       6
  120
Align it to the tens of the two digit number as you multiply it there. To avoid confusion you can add 0 below the number 6

Last step add the products.

   42
x   3
-------
     6
+120
--------
126

And yeah you got 126. :) 

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