The 11 Rule

 To multiply any two digit number by 11:

 For this example we will use 34.

        ·      S  Separate the two digits in you mind (3__4).

        ·    Notice the hole between them!

        ·      Add the 6 and the 4 together (3+4=7)

        ·       Put the resulting 7 in the hole 374. That’s it! 11 x 34=374

The only thing tricky to remember is that if the result of the addition is greater than 9, you only put the “ones” digit in the hole and carry the “tens” digit from the addition. For example 11 x 57 … 5__7 … 5+7=12 … put the 2 in the hole and add the 1 from the 12 to the 5 in to get 6 for a result of 627 … 11 x 57 = 627

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