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Speed-Multiplication by 11
with no carries

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This is going to be infinitely easier than any other multiplications you have ever done.

• First of all, you are going to get the answer without any multiplying!
  
• Second, you are going to get the answer without writing anything, or showing any "work." (There is no work, in the usual sense.)

• Third, you are going to be able to get the answer quicker than most people would be able to type the problem into a calculator.

  In this lesson, we're going to multiply a large number by 11. It is going to happen almost instantly. There will be no "multiplication tables." etc. It is the beginning example of how some speed-math techniques work.

As you read the steps, click the start button to illustrate them.

  This method works with any number, no matter how long or short, times 11, unless any two digits next to each other in the problem add up to more then 9. In that case, you would have to know a little twist on the above lesson. That is on the next page. Click in the box below to access that page.

In the near future I will have a page up about why it works and how you can use it to learn how to do other numbers. In the meantime practice it with a few long, random numbers times 11.

   Hint:
   Don't be tempted to actually write the invisible zeros or the carrys (if there are any). Schools make you "show the work." That may be OK for the first grades, but they should have weaned you away from that by third grade. Don't use the crutch of writing what your mind is capable of doing mentally. Doing it in your head develops you skill at visualization. Getting good at visualizing will help you develop concentration and general intelligence. Don't mess that up with mental crutches like writing what you should be able to do in your head. Learning to do things in your head easily is what this site is about.

 This, of course, is the method for multiplying numbers by 11. A lot of ignorant teachers like to shoot this method down, because it is "just a trick" or because "it doesn't work with other numbers."

Any time you do something exceptional, mediocre people will have a problem with it. That is fine, but the REAL problems start when they try to make their problem your problem. To keep them from ruining a good thing for you, Here are some ways to think about the flak they will give you: click here for your "flak jacket."

click here for the next interactive lesson

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