How to Quickly Multiply Single Digits by

Step-by-Step Guide

1. 1

   Step 1: Remember that any number multiplied by 1 is the number itself.

   No matter how tricky 9 is, it can't escape the fact that 1x9 will always equal
   9. , Don't try to multiply 9x9 before you learn 9x2 because it is a lot easier to think of math like a ladder.
   
   You should take each step to the top because if you try to skip steps you may just fall back and have to start over., When you subtract one from your digit, you will have the first digit in the product.
   
   For example, when you want to know the product of 9x2, subtract 1 from 2 and you will know your answer starts with a
   1., If you subtract the first number in your product from 9 you will get the second number in your product.
   
   We found out the first number in the product of 9x2 is 1 by subtracting 1 from 2 and 9-1=8., You found the first digit of your answer to be 1 and then your next to be
   8.
   
   This means the product of 9x2 is
   18.
   
   Note that the sum of the digits always equals
   9.
   
   Even with multiplying 9 by numbers higher than ten, if you add all the digits in a multiple of 9, and then add the digits again if there are more than one, and so on, you will always eventually end up with
   9.
   
   For example, 9 x 15,873 is equal to 142,857.
   
   Add the digits of this number together, and get
   27.
   
   Add the digits of this together and you will end up with
   9. ,
2. 2

   Step 2: Start simple and work your way up.

3. 3

   Step 3: Subtract 1 from the single digit you've chosen to multiply time 9 (starting with 2).

4. 4

   Step 4: Subtract the first digit of your answer from 9.

5. 5

   Step 5: Put your numbers together.

6. 6

   Step 6: Calculate other single multiplication problems with 9 with this method and you'll be able to solve them in your head in no time!

Detailed Guide

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