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### Primes and Number Riddles

```
Date: 4/15/96 at 21:17:0
From: Anonymous
Subject: Pre Algebra: Finding primes as the result of solving number
riddles

find the proper method to solve this and future riddles like it.
Thanks and here is the problem as it appears in its entirety.

Three different one-digit primes
Produce me, if you're using times;
Two answers - and nothing else
rhymes.

Thank you very much for your assistance!
```

```
Date: 4/22/96 at 20:19:12
From: Doctor Joshua
Subject: Re: Pre Algebra:  Finding primes as the result of solving
number riddles

Hi!

By process of elimination, there are only four one-digit primes:
2,3,5, and 7.

Multiplying any three of these together:

2X3X5  =  30  Sum of digits = 3, this works!

2X3X7  =  42  Sum of digits = 6

2X5X7  =  70  Sum of digits = 7, this works as well.

3X5X7  =  105 Sum of digits = 6

So the answers to the riddle are 30 and 70.

-Doctor Joshua,  The Math Forum
Check out our web site!  http://mathforum.org/dr.math/
```
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High School Puzzles

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