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**ericnumberking****Member**- From: Vancouver
- Registered: 2018-02-06
- Posts: 5

This is a quick way to multiply two-digit numbers by 11 in your head. Created by a banker believe it or not.

Let's say you are trying to multiply 72 x 11.

Which equals to 792

- Split 72 in to two digits (72 becomes 7 and 2).

- Then add these two digits together (7+2=9)

- Now place 9 in the middle of 7 and 2 and what do you get? 792

Pretty sweet eh?

Let's try that with another number . . . 56 x 11

which equals to

- 56. So 5 And 6

- 5 + 6 is 11 (Just carry the one to the first 5. So 5 becomes 6)

- Answer is (Drumroll . . .) = 616

Try it out!

*Last edited by ericnumberking (2021-01-07 20:35:59)*

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