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### 1 2 3 4 5 6 7 8 9 0 = 100

```
Date: 01/24/2002 at 05:52:15
From: Connie

Dear Dr. Math,

1 2 3 4 5 6 7 8 9 0 = 100

Leave the numerals in this order. Place only addition and subtraction
signs to make it a true statement.

I have figured out that you can leave some of the numbers, for example
you don't have to put signs in every one of them. You can say:

123 - 4 + 5 + 6 + 7890 = 100

or something like that.

Connie Chen
```

```
Date: 01/27/2002 at 10:59:17
From: Doctor Steve

Dear Connie Chen,

I like what you have figured out. My first thought is that there must
be lots of ways to do this and I think the key is to pick some
combination as a starting point and then see if I can make the other
numbers work out.

In this case I tried starting with a simple combination that I know
would make 100, and see if I can make the rest of the numbers cancel
each other out.

If I use 90, then I just need 10 more to make 100. I could add 8 and 2
to make 10.

So far I have:

+ 2                + 8 + 90 = 100

Then all I need to do is figure out how 1,3,4,5,6,and 7 can be
combined to cancel each other out. So I'll use my method again and
pick a combination and see if I can make it work.

6 + 7 is 13. Can I make the other numbers equal to 13? Hey,
1 + 3 + 4 + 5 is 13. So, I just need to subtract those.

- 1 - 3 - 4 - 5 + 6 + 7

Perfect. Now I could just combine those numbers  with my original
choices and I'll have 100. Do you see how?

Try another combination and see if you can make it work.

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