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### Using the Distributive Property

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Date: 08/23/2001 at 20:17:06
From: Jennifer Cmajdalka
Subject: Distributive property

My math teacher told us to work problems like this:

a(b-c)= ab-ac

If we do them like that, then how do I do these problems?

67(40)
AND
210(800)

I hope you can help me! She said not to do multiplication on that, but
to work it the way you work a distributive propery. HELP! Thanks!

Jen
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```
Date: 08/24/2001 at 16:33:52
From: Doctor Ian
Subject: Re: Distributive property

Hi Jen,

I think what she wants you to do is to break one of the terms up into
a sum, e.g.,

(49)70 = (40 + 9)70

= (40)70 + (9)70

= 2800 + 630

= 3430

Actually, this is a good trick to use to do multiplication in your
head, so it's worth spending a little time practicing it.

But mostly, I think she wants you to get used to looking for
opportunities to apply the distributive property, since once you get
to algebra, it's going to be one of your best friends!

Does this help?

- Doctor Ian, The Math Forum
http://mathforum.org/dr.math/
```

```
Date: 08/24/2001 at 20:17:06
From: Jenny L Cmajdalka
Subject: Re: Distributive property

Thank you for helping me! That is what she wanted!

Jen
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