Easy Puzzle #28 - One Possible Solution Approach…
	NB:  There is only one final solution to this Sudoku puzzle…
	Rules: Place a number from 1-9 in each empty cell so that each row, each column AND each 3x3 block contains all the numbers from 1-9.
	A	B	C	D	E	F	G	H	I
1
2	AA			BB			CC				Reference to 3x3 Blocks AA, BB & CC
3
4
5	DD			EE			FF				Reference to 3x3 Blocks DD, EE & FF
6
7
8	GG			HH			II				Reference to 3x3 Blocks GG, HH & II
9
	A	B	C	D	E	F	G	H	I
1	8	4			7		9				Easy Puzzle #28 - October 28, 2005
2	9	7		4			5	1			Original puzzle as published © joe-ks.com
3					1			4	8
4		2	9	1
5		6	4			8	1
6	3					7	2	5
7	2	3			4	9	8
8			6			1		9	5
9			5		6			7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7		9				Step 1: #9 is in Rows 1 & 2: #9 MUST go in Cell D3
2	9	7		4			5	1			(#9 in Column F @ F7 excludes use of Cell F3)
3				9	1			4	8
4		2	9	1							Step 2: #5 is in Rows 8 & 9: #5 MUST go in Cell D7…
5		6	4			8	1
6	3					7	2	5
7	2	3		5	4	9	8
8			6			1		9	5
9			5		6			7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7		9				Step 3: #9 is in Columns A & C: #9 MUST go in Cell B9
2	9	7		4			5	1			(#9 in Row 8 @ H8 excludes use of Cell B8)
3				9	1			4	8
4		2	9	1
5		6	4			8	1
6	3					7	2	5
7	2	3		5	4	9	8
8			6			1		9	5
9		9	5		6			7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7		9				Step 4: #7 is in Rows 1 & 2: #7 MUST go in Cell G3…
2	9	7		4			5	1
3	6			9	1		7	4	8		Step 5: #6 is in Columns B & C: #6 MUST go in Cell A3…
4		2	9	1
5		6	4			8	1
6	3					7	2	5
7	2	3		5	4	9	8
8			6			1		9	5
9		9	5		6			7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7		9				Step 6: Block AA needs #5: #5 MUST go in Cell B3
2	9	7		4			5	1			(#5 in Column C @ C9 excludes use of Cells C1, C2 & C3)
3	6	5		9	1		7	4	8
4		2	9	1							Step 7: #7 is in Columns E & F: #7 MUST go in Cell D8
5		6	4			8	1				(#7 in Row 9 excludes use of Cell D9)
6	3					7	2	5
7	2	3		5	4	9	8
8			6	7		1		9	5
9		9	5		6			7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7		9				Step 8: Block BB needs #8: #8 MUST go in Cell E2
2	9	7		4	8		5	1			(#8 in Row 1 @ A1 excludes use of Cells D1 & F1, &
3	6	5		9	1		7	4	8		#8 in Column F @ F5 excludes use of Cells F1, F2 & F3)
4		2	9	1
5		6	4			8	1				Step 9: #7 is in Rows 8 & 9: #7 MUST go in Cell C7…
6	3					7	2	5
7	2	3	7	5	4	9	8
8			6	7		1		9	5
9		9	5		6			7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7	5	9				Step 10: Block GG needs #1: #1 MUST go in Cell A9
2	9	7		4	8		5	1			(#1 in Row 8 @ F8 excludes use of Cells A8 & B8)
3	6	5		9	1		7	4	8
4		2	9	1							Step 11: #5 is in Rows 2 & 3: #5 MUST go in Cell F1
5		6	4			8	1				(#5 in Column D @ D7 excludes use of Cell D1)
6	3					7	2	5
7	2	3	7	5	4	9	8
8			6	7		1		9	5
9	1	9	5		6			7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7	5	9				Step 12: Complete Block GG: need #s 4 & 8…
2	9	7		4	8		5	1			#8 can't go in Cell A8 (cf #8 in Column A @ A1), so
3	6	5		9	1		7	4	8		#8 MUST go in Cell B8, & therefore #4 MUST go in Cell A8
4		2	9	1
5		6	4			8	1				Step 13: #8 is now in Columns A& B: #8 MUST go in Cell C6
6	3		8			7	2	5
7	2	3	7	5	4	9	8				Step 14: #4 is now in Rows 7 & 8: #4 MUST go in Cell G9…
8	4	8	6	7		1		9	5
9	1	9	5		6		4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7	5	9				Step 15: #2 is in Rows 7 & 9: #2 MUST go in Cell E8…
2	9	7		4	8		5	1
3	6	5		9	1		7	4	8		Step 16: #1 is in Rows 4 & 5: #1 MUST go in Cell B6…
4		2	9	1
5		6	4			8	1
6	3	1	8			7	2	5
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1		9	5
9	1	9	5		6		4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7	5	9				Step 17: Complete Block HH: need #s 3 & 8…
2	9	7		4	8		5	1			#8 can't go in Cell F9 (cf #8 in Column F @ F5), so
3	6	5		9	1		7	4	8		#8 MUST go in Cell D9, & therefore #3 MUST go in Cell F9
4		2	9	1
5		6	4			8	1				Step 18: #3 is now in Rows 7 & 9: #3 MUST go in Cell G8…
6	3	1	8			7	2	5
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4			7	5	9				Step 19: Complete Row 3: need #s 2 & 3…
2	9	7		4	8		5	1			#3 can't go in Cell F3 (cf #3 in Column F @ F9), so
3	6	5	3	9	1	2	7	4	8		#3 MUST go in Cell C3, & therefore #2 MUST go in Cell F3
4		2	9	1
5		6	4			8	1
6	3	1	8			7	2	5
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4		3	7	5	9				Step 20: Complete Block BB: need #s 3 & 6…
2	9	7		4	8	6	5	1			#3 can't go in Cell F2 (cf #3 in Column F @ F9), so
3	6	5	3	9	1	2	7	4	8		#3 MUST go in Cell D1, & therefore #6 MUST go in Cell F2
4		2	9	1
5		6	4			8	1
6	3	1	8			7	2	5
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4		3	7	5	9				Step 21: Complete Column D: need #s 2 & 6…
2	9	7		4	8	6	5	1			#2 can't go in Cell D6 (cf #2 in Row 6 @ G6), so
3	6	5	3	9	1	2	7	4	8		#2 MUST go in Cell D5, & therefore #6 MUST go in Cell D6
4		2	9	1
5		6	4	2		8	1
6	3	1	8	6		7	2	5
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4		3	7	5	9				Step 22: Complete Row 6: need #s 4 & 9…
2	9	7		4	8	6	5	1			#4 can't go in Cell E6 (cf #4 in Column E @ E7), so
3	6	5	3	9	1	2	7	4	8		#4 MUST go in Cell I6, & therefore #9 MUST go in Cell E6
4		2	9	1
5		6	4	2		8	1		9		Step 23: #9 in now in Rows 4 & 6: #9 MUST go in Cell I5
6	3	1	8	6	9	7	2	5	4		(#9 in Column H @ H8 excludes use of Cell H5)
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4		3	7	5	9				Step 24: Block EE needs # 4: #4 MUST go in Cell F4
2	9	7		4	8	6	5	1			(#4 in Column E @ E7 excludes use of Cells E4 & E5)
3	6	5	3	9	1	2	7	4	8
4		2	9	1		4			7		Step 25: #7 is in Columns G & H: #7 MUST go in Cell I4…
5		6	4	2		8	1		9
6	3	1	8	6	9	7	2	5	4
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4		3	7	5	9				Step 26: #7 is in Rows 4 & 6: #7 MUST go in Cell A5…
2	9	7		4	8	6	5	1
3	6	5	3	9	1	2	7	4	8		Step 27: Complete Block DD: #5 MUST go in Cell A4...
4	5	2	9	1	3	4			7
5	7	6	4	2	5	8	1		9		Step 28: #5 is now in Rows 4 & 6: #5 MUST go in Cell E5...
6	3	1	8	6	9	7	2	5	4
7	2	3	7	5	4	9	8				Step 29: Complete Block EE: #3 MUST go in Cell E4...
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4		3	7	5	9				Step 30: #3 is in Rows 4 & 6: #3 MUST go in Cell H5...
2	9	7		4	8	6	5	1	3
3	6	5	3	9	1	2	7	4	8		Step 31: #3 is now in Columns G & H: #3 MUST go in Cell I2
4	5	2	9	1	3	4			7		(#3 in Row 1 @ D1 excludes use of Cell I1)
5	7	6	4	2	5	8	1	3	9
6	3	1	8	6	9	7	2	5	4
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4	1	3	7	5	9				Step 32: #1 is in Rows 2 & 3: #1 MUST go in Cell C1...
2	9	7	2	4	8	6	5	1	3
3	6	5	3	9	1	2	7	4	8		Step 33: Complete Column C: #2 MUST go in Cell C2…
4	5	2	9	1	3	4			7
5	7	6	4	2	5	8	1	3	9
6	3	1	8	6	9	7	2	5	4
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4	1	3	7	5	9	2	6		Step 34: Complete Row 1: need #s 2 & 6…
2	9	7	2	4	8	6	5	1	3		#2 can't go in Cell I1 (cf #2 in Column I @ I9), so
3	6	5	3	9	1	2	7	4	8		#2 MUST go in Cell H1, & therefore #6 MUST go in Cell I1
4	5	2	9	1	3	4	6		7
5	7	6	4	2	5	8	1	3	9		Step 35: Complete Column G: #6 MUST go in Cell G4...
6	3	1	8	6	9	7	2	5	4
7	2	3	7	5	4	9	8
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4	1	3	7	5	9	2	6		Step 36: Complete Block II: need #s 1 & 6…
2	9	7	2	4	8	6	5	1	3		#6 can't go in Cell I7 (cf #6 in Column I @ I1), so
3	6	5	3	9	1	2	7	4	8		#6 MUST go in Cell H7, & therefore #1 MUST go in Cell I7
4	5	2	9	1	3	4	6	8	7
5	7	6	4	2	5	8	1	3	9		Step 37: Complete Block FF (& Puzzle):
6	3	1	8	6	9	7	2	5	4		#8 MUST go in Cell H4.
7	2	3	7	5	4	9	8	6	1
8	4	8	6	7	2	1	3	9	5
9	1	9	5	8	6	3	4	7	2
	A	B	C	D	E	F	G	H	I
1	8	4	1	3	7	5	9	2	6	45	Final Proof:
2	9	7	2	4	8	6	5	1	3	45	- All Rows add up to 45;
3	6	5	3	9	1	2	7	4	8	45
4	5	2	9	1	3	4	6	8	7	45
5	7	6	4	2	5	8	1	3	9	45
6	3	1	8	6	9	7	2	5	4	45
7	2	3	7	5	4	9	8	6	1	45
8	4	8	6	7	2	1	3	9	5	45
9	1	9	5	8	6	3	4	7	2	45
	45	45	45	45	45	45	45	45	45		- All Columns add up to 45;
	45			45			45				- All 3x3 Blocks add up to 45…
	45			45			45
	45			45			45