Printing Error:
First observe that 79 can only be 9x8+7 in some order, and with two 
of those numbers unavailable, 80 can only be 8x2x5 in some order, so 
we can place the 8. If the 9 goes at the bottom, 31 can only be 4+3x9 
but 1, 6, and 7 cannot make 27 so this is wrong and 7 goes at the bottom. 
Now 31 can be 4x6+7 or 3+4x7. 27 can be 1x3x9 or 3x6+9. The only way 
to avoid duplication is to use the first of each pair of possibilities.

We still have to properly order the first two numbers of each row. 
9 can be made as 3+2+4, 1+2+6, 1+2x4, or 1x5+4. 21 can be made as 
3x5+6 or 1+5x4. Only 3x5+6 and 1+2x4 avoid duplication.

3 x 1 x 9 =27
x   +   x    
5 x 2 x 8 =80
+   x   +    
6 x 4 + 7 =31
=   =   =    
21  9   79   
Joseph DeVincentis
-------------------------------------------------
Here's a solution I found to this puzzle:

3 x 1 x 9
+   +   +
5 x 2 x 8
x   +    +
4 x 6 + 7

In case the ascii formatting doesn't work, here's what i have, row by row:
"3 times 1 times 9 row
plus plus plus row
5 times 2 times 8 row
times plus plus row
4 times 6 plus 7"
Thanks for your time,
Joey
------------------------------------------------
3 * 1 * 9 =27
*   +   *
5 * 2 * 8 =80
+   *   +
6 * 4 + 7 =31
=   =   =
21  9   79

John Dalbec
------------------------------------------------
Hi Ed,
Here's a solution to Bryce Herdt's Printing Problem problem.

   3 * 1 * 9 = 27
   *   +   +
   5 * 2 * 8 = 80
   +   *   +
   6 * 4 + 7 = 31
   =   =   =
  21   9  79

Thanks again to you and Bryce for the entertainment, Matt Sheppeck
------------------------------------------------
Hi Ed,
This little puzzle stumped me for a while.
However, 80 can be assembled only with
the 5*2*8 and then 79 has only one solution
also.
 
3  *  1  *  9
*      +     *
5  *  2  *  8
+     *      +
6  *  4  +  7
 
Dick Saunders Jr.
-------------------------------------------------

Solution:

3 x 1 x 9 = 27

x    +   x

5 x 2 x 8 = 80

+   x    +

6 x 4 + 7 = 31

=   =   =

21  9   79


Alan Lemm

--------------------------------------------------

3 * 1 * 9 =27
*   +   *
5 * 2 * 8 =80
+   *   +
6 * 4 + 7 =31
=   =   =
21  9   79

This assumes normal operator precedence of * before +

Kirk Bresniker
--------------------------------------------------

In rows: 3x1x9=27
         5x2x8=80
         6x4+7=31
In columns: 3x5+6=21
            1+2x4=9
            6x4+7=1
Simple but ingenious because pleasant for solving - logically, step by step.
Congratulations!
Marek Penszko
Warsaw, Poland

---------------------------------------------------
Printing Error Answer:
 
3x1x9
x + x
5x2x8
+ x +
6x4x7
 
Colin Sturm
Michael Matlock

---------------------------------------------------

I don't know if the formating will work, but here are the equations

Verticle from left to right:
(3 * 5) + 6 = 21
1 + (2 * 4) = 9
(9 * 8) + 7 = 79

Horizontal from top to bottom:
3 * 1 * 9 = 27
5 * 2 * 8 = 80
(6 * 4) + 7 = 31

So the grid looks like:

319
528
647

and the operations

 * *
* + *
 * *
+ * +
 * +

Christopher Johnson 

------------------------------------------------------

3 * 1 * 9 = 27
*   +   *
5 * 2 * 8 = 80
+   *   +
6 * 4 + 7 = 31
=   =   =
21  9   79

Wang Zirui

------------------------------------------------------

Hi Ed,

Here's the solution to Bryce Herdt's puzzle:

3 x 1 x 9

x   +   x

5 x 2 x 8

+   x   +

6 x 4 + 7

Daniel Scher