CCSS.MATH.CONTENT.3.OA.D.9 Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations.
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Today we'll be learning how to identify and use arithmetic patterns to multiply.
We'll learn about several different strategies to multiply by 9.
Take a look at the table below. Notice the pattern that occurs with the product of a multiple of 9. Think how you can use this information to help you multiply or check your answer.
The number 9 truly is a special number.
Now take that information and take a look at the poster on this page called "The 9s Trick"
Noticing these patterns lets us do a number of different.
When counting by 9s, we can also count by 10s and subtract 1.
This is called the 10 More, 1 Less strategy.
9×n = (10×n) – (1×n)
Jump into your math notebook and answer this question!
Why is it important to know several strategies for solving larger multiplication facts?