# The 11 times trick!

By lucas10odak

@lucas10odak (268)

United States

December 23, 2008 9:33pm CST

we all know the trick when multiplying by ten - add 0 to the end of the number, but did you know that there is equally easy trick for multiplying a two digit number by 11? This is it:
Take the original number and imagine a space between the two digits (in this example we gonna use 72)
7_2
Now add the two numbers together and put them in the middle:
7_(7+2)_2
That is it - you have the answer:792
If the numbers in the middle add up to a 2 digit number , just insert the second number and 1 to the first:
9_(9+9)_0
10_8_9
It works every time!
Enjoy

1 response

@NonaSaile (926)

• Philippines

29 Dec 08

I knew of the trick about multiplying by ten, but not about multiplying by 11. Thanks for the tip, I have noted it down. It will be great to pass on to my nephews and nieces still in school. Any kid still in school for that matter.
Happy mylotting!