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Lesson 10 - Nines (Method 1)
Using your fingers 

This is the one less = nine method

  • Subtract one from the number you are multiplying by.  9 x 5  (One less than 5 is 4) 

  • The first number in the answer is 4.  The two numbers that make up the answer will equal 9.  So 4 + __ = 9  (5)

  • The last number in the answer is 5.

  • 9 x 5 = 45

    • One less than 5 is 4 (45)

    • The answer adds up to nine. 4 + 5 = 9

Here is another example

  • 9 x 8

  • One less than 8 is 7. So the first number in the answer is 7.

  • 7 + 2 equals 9.  So the second number in the answer is 2.
  

Use the chart below to quiz yourself. 
Look at the fact below and think of the answer.  Check it by hovering the mouse over the problem.
   
  0 1 2 3 4 5 6 7 8 9
0                  
1                  
2                  
3                  
4                  
5                  
6                  
7                  
8                  
9

On to Lesson 11

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