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So we need to figure out what 46 plus 43 is.

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Let me write it down again and I'll write it like

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this: 46 plus 43.

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What we do here is we just first look at the ones place.

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We literally have 6 ones plus 3 ones, or you could say 6 and

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3, and 6 plus 3 is just 9.

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6 plus 3 is 9, so we have 9 ones.

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And then you go to the tens place, and there's two ways to

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think about it.

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You could view this as 4 plus 4 is equal to 8, but really,

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the reality of what we're doing since we're operating in

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the tens place, this is really 40 plus 40 is equal to 80.

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And we could do the same problem expanded out.

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This is the same thing as 40 plus 6.

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We've seen this before, right?

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That's what 46 is.

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And then 43 is the same thing as 40 plus 3.

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We've expanded these out before.

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And so when you add them, when you add a 6 plus a

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3, you get a 9.

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When you add a 40 plus a 40, you get an 80.

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So you get 80 plus 9, which is 89.

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And the whole reason why I did this is I wanted to show you

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that when you're adding 4's in the tens place, you're really

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adding 40's.

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The fact that it's in the tens place represents-- or the fact

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that the 4 is in the tens place shows that

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it represents 40.

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The fact that the 8's there shows that it represents 80.

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