I think that they are about 40 past draws.
First I am going to count the singles and the doubles (beware of mistakes if any).
Minnesota
Tue, Apr 28, 2015 1-3-2 Single
Mon, Apr 27, 2015 2-0-2 Double 1
Sun, Apr 26, 2015 7-7-0 Double 2
Sat, Apr 25, 2015 4-0-1 Single
Fri, Apr 24, 2015 5-7-6 Single
Thu, Apr 23, 2015 0-1-9 Single
Wed, Apr 22, 2015 2-0-0 Double 3
Tue, Apr 21, 2015 0-0-2 Double 4
Mon, Apr 20, 2015 6-2-5 Single
Sun, Apr 19, 2015 7-4-4 Double 5
Sat, Apr 18, 2015 3-4-9 Single
Fri, Apr 17, 2015 3-5-6 Single
Thu, Apr 16, 2015 1-3-2 Single
Wed, Apr 15, 2015 4-8-9 Single
Tue, Apr 14, 2015 0-5-0 Double 6
Mon, Apr 13, 2015 1-1-7 Double 7
Sun, Apr 12, 2015 7-0-7 Double 8
Sat, Apr 11, 2015 5-5-7 Double 9
Fri, Apr 10, 2015 3-0-9 Single
Thu, Apr 09, 2015 8-4-8 Double 10
Wed, Apr 08, 2015 7-3-4 Single
Tue, Apr 07, 2015 8-1-2 Single
Mon, Apr 06, 2015 2-7-4 Single
Sun, Apr 05, 2015 0-2-9 Single
Sat, Apr 04, 2015 3-8-6 Single
Fri, Apr 03, 2015 4-0-9 Single
Thu, Apr 02, 2015 9-2-3 Single
Wed, Apr 01, 2015 6-9-4 Single
Tue, Mar 31, 2015 0-5-0 Double 11
Mon, Mar 30, 2015 2-4-7 Single
Sun, Mar 29, 2015 3-7-1 Single
Sat, Mar 28, 2015 0-8-3 Single
Fri, Mar 27, 2015 1-3-2 Single
Thu, Mar 26, 2015 6-5-0 Single
Wed, Mar 25, 2015 3-8-6 Single
Tue, Mar 24, 2015 5-7-2 Single
Mon, Mar 23, 2015 8-9-8 Double 12
Sun, Mar 22, 2015 6-1-4 Single
Sat, Mar 21, 2015 5-4-6 Single
Fri, Mar 20, 2015 9-8-7 Single
There seem to be 12 Doubles, so there must be 28 Singles.
There are 720 Singles, 270 Doubles and 10 Triples, so the Singles are 72% and the Doubles are 27%.
On 40 past draws 0.4 is 1%
So 0.4 X 72 = 28.8 or 29 past draws (rounded).
So as we can see, on those 40 past draws, the expected 72% for Singles almost came out.
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That might be a possible indication that this particular pick 3 game is a "fair" game, I said might be, as Singles and Doubles is only 1 thing to check out of many possible things such as Digits, Pairs, Low-High, Even-Odd, Etc.
Sometimes 1 or more things check out right, but some other things don't check out right.
The more things that check out right as they should be expected to be, maybe the more of a chance that a particular game might be "Fair" to play.
That is my own opinion, so it might or might not be correct.
In the past I already posted this same thing.
As I said "What really happens is what you (we) see on the past draws".
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Will post some more on this thread.