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avatar+49 

Let's play mini-Sudoku!

We wish to place an "X" in four cells, such that there is exactly one "X" in each row, column, and 2x2 outlined box.

For example:

In how many ways can we do this?

(Terminology: A cell is one of small 1x1 spaces. A box is one of four outlined 2x2 group of cells.)

 Jul 8, 2017
 #1
avatar+111387 
+3

 

This was answered a while back, but the answer ends up being 16

 

4 ways to place the X in the top row

2 ways to place the X  in the second row [ in the other 2 x 2  box not occupied by the first X ]

2 ways to place the X in the  third row  [ we can choose either of the two empty columns]

Only 1 way  to place the last X in the last empty column

 

So   ....4 x 2 x 2 x 1   =  16

 

 

 

cool cool cool

 Jul 8, 2017
 #2
avatar+8965 
+2

Here's the older one if it helps any:   https://web2.0calc.com/questions/question-asap   smiley

 Jul 9, 2017

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