Mental Calculation

Multiplying two complimentary numbers(numbers which are same except the right most digits and the right most digits add to 10). Some of the complimentary pairs are 23 and 27, 44 and 46, 54 and 56, 112 and 118 etc.

Let us understand the trick with this example: 112 X 118 Step 1: Take the right most digits and multiply them together. The result forms right most digits of the answer. So, 2X8=16.

Step 2: Then take the first number without its right most digit, which in this case is 11. Multiply it with the next higher whole number. In our example it would be 11X12= 132(using the multiplication trick for 11). The result will give us the initial digits of the answer. Hence, the answer would be 13216.

Practice a few more and share it with your children to make them more confident at mental arithmetic. Happy multiplication until I learn and share another interesting trick with you all!!. For other interesting articles, pls visit social network FB site Celebrating Maths.