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What is the Number?

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Date: 29 Mar 1995 10:05:01 -0500
From: JOSEPH CAPASSO
Subject: help

I'm in 7th grade, need someone to explain how to solve
this simple word problem.

"You know that a certain 5-digit number is a power of 7
and that its ones digit also is 7.  What is the number?"

If you can help me, I have a couple more....

Thanks
Joe
```

```
Date: 29 Mar 1995 13:27:31 -0500
From: Dr. Ken
Subject: Re: help

Hello there!

Well, I think that the easiest way to solve this problem is
probably to start writing down the powers of 7: 7, 49, 343,
etc.  How many of them have five digits?  It may take a
minute or two to write them down, but once you do that, it
will become pretty clear what the answer is.

Write back if you need more help!

-Ken "Dr." Math
```
Associated Topics:
Middle School Word Problems

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