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Teach your children math tricks and have fun
Times Eleven Trick
The best way to learn math is to have fun while learning. This trick may not help your child in their studies and homework but it gives them a chance to see that math can be fun. And if it's fun there is a better chance they will be motivated to learn.
One of the simplest muliplaction tricks to learn is the "Times Eleven trick." and there isn't any multiplication to it. Take any two-digit number and multiply it by eleven and you know the answer by using simple one-digit addition. Your child doesn't need to know multiplication to know this trick.
You have a two-digit number and you are multiplying it by eleven. Without actually multiplying the number, take the number (not the eleven) and add them together and then place the answer between the two numbers. For example:
Twenty-two times (multiplied by) Eleven is the problem. The answer is two, four (two plus two), two, or two hundred and fourty two. Do you see how it works?
Let's try a different number. Try Thirty-one times (multiplied by) Eleven. The first thing you do is add Three plus One equals Four (3+1=4). So your answer will be Three, Four, One (341). Put the Four in between the Three and the One and you get Three Hundred and Fourty One. It was really that easy.
It gets a little bit more difficult using numbers that add up to be ten or more. But don't worry, it's still addition and not multiplication. All you need to do is carry the one over to the first number. For example: Sixty Four multiplied by Eleven is (Six, six plus for is ten, and four) so leave the zero in the middle and add the one to the first number. The answer will be 7, zero, four (704).
704 Start with 6, (6+4=10), leave the zero, add the 1 to the first number, and 4
Seven, zero, four.
Now try some more:
693 Six, (6+3=9), Three
Here is the hardest "Times Eleven trick" you will ever have:
Nine, (9+9=18) leave the eight and add one to the first digit, the last digit will be 9.
10, 8, 9
So now that you know the trick, try it with your child. Have you child take a calculator. Have your child make up a two digit number to multiply by Eleven. They will think you have a magic gift when they see you adding the numbers together in your head faster than your child can type the number into the calculator. After several examples and after your child is amazed by your magical gift of mental magic, come clean and explain how they can do it too.
A good magician never reveals their secret but a good math teacher does.Be a good math teacher and show them that they can take a scary two digit number and multiply it with another two digit number in their head and get to correct answer. It makes math fun and it takes the fear out of math problems they may not be familiar with.
Every child I taught this trick to always went running to their friends and did the same magic act. They amazed their friends and then taught their friends.
Enjoy, have fun, and learning math can always be fun.