The 11 times trick!
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
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!