Adding Numbers Within 100
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For this lesson, we'll be working with easy numbers just to get you used to how this stuff works.

We're going to work with everything stacked because this is what you'll always do with bigger numbers.

I'm also going to have you do something really weird...  I'm going to have you work backwards! 

I'm going to have you add the ones first... then the tens.  You'll have to do it this way when the numbers get harder.

Let's jump in!

23+51

Stack them and line everything up:

23+51

Add down the stripes...  Do the ones first, then the tens:

23+51 23+51

so, 23+51=74

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