Multiplication Tricks – Multiplying by 11

August 30th, 2009 by Math Tricks | Filed under Multiplication Tricks.

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One of the easiest multiplication tricks that I know of is also one of the most impressive.  It is the multiplication of two-digit numbers, and, like many other math tricks, there is an easy rule that you can use to solve problems of this sort very quickly in your head.

An Example:

44 x 11

The technique for quickly solving multiplication problems involving any two-digit number by 11 is easy to remember.  Simply add the two digits and insert the result in between the two digit number.

In our example:

44 x 11

4 + 4 = 8, so simply insert “8” between “4” and “4”:

484

So then we have quickly found that
44 x 11 = 484

Now wasn’t that easy?!

4 Responses to “Multiplication Tricks – Multiplying by 11”

1. Epiphany Luhteran Church & School | 10/03/10

Hi, I taught this trick to my 5 year old last night and he had a blast showing off to his mother and his older brother. They were both stunned. I’m trying hard to have these boys grow up inspired by math. Thanks for the help!