[b said:
Quote[/b] (jimscott @ Mar. 30 2006,9:06)]0 0 0 6 0 0 0 3 2
0 5 6 8 0 0 7 0 0
8 0 7 9 1 0 0 5 0
0 0 2 3 0 0 0 6 7
9 0 0 5 0 4 0 0 3
7 4 0 0 0 6 1 0 0
0 3 0 0 2 8 5 0 1
0 0 8 0 0 5 9 4 0
4 1 0 0 0 9 0 0 0
for this one, the first thing that stands out at me is the three 3x3 boxes that are on the left. The top one has a 7 in the right column, the middle one has a 7 in the left column, and the bottom one has no 7 yet. Since we can see that the right and left columns already have 7s in them, we can conclude that the 7 for the bottom box must be in the middle. And, there is only one blank spot for the middle column, so that spot is a 7:
0 0 0 6 0 0 0 3 2
0 5 6 8 0 0 7 0 0
8 0 7 9 1 0 0 5 0
0 0 2 3 0 0 0 6 7
9 0 0 5 0 4 0 0 3
7 4 0 0 0 6 1 0 0
0 3 0 0 2 8 5 0 1
0
7 8 0 0 5 9 4 0
4 1 0 0 0 9 0 0 0
Same sort of thing for the 3x3 boxes on the right side of the puzzle. The top and middle ones have 3s, in the middle and right columns respectively. But the bottom one doesn't, and there's only one blank spot in the left column, which must be a 3.
0 0 0 6 0 0 0 3 2
0 5 6 8 0 0 7 0 0
8 0 7 9 1 0 0 5 0
0 0 2 3 0 0 0 6 7
9 0 0 5 0 4 0 0 3
7 4 0 0 0 6 1 0 0
0 3 0 0 2 8 5 0 1
0 7 8 0 0 5 9 4 0
4 1 0 0 0 9
3 0 0
Now, on the bottom 3 boxes, the left and the right both have 3s, on the top and bottom rows respectively. But the middle box doesn't. And, there are 2 blank spots in that middle row. But if you look at the columns that those blank spaces are in, you can see that one of them already has a 3. So, it must be the OTHER one.
0 0 0 6 0 0 0 3 2
0 5 6 8 0 0 7 0 0
8 0 7 9 1 0 0 5 0
0 0 2 3 0 0 0 6 7
9 0 0 5 0 4 0 0 3
7 4 0 0 0 6 1 0 0
0 3 0 0 2 8 5 0 1
0 7 8 0
3 5 9 4 0
4 1 0 0 0 9 3 0 0
So you want to keep jumping around the puzzle like that, using the information you already have to narrow down the possibilities.