| Easy Puzzle #11 - 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 | 6 | 3 | 8 | Easy Puzzle #11 - October 11, 2005 | |||||||
| 2 | 6 | 3 | 4 | 8 | 7 | 5 | One possible Solution Method follows below… | ||||
| 3 | 5 | 2 | 7 | 9 | 4 | ||||||
| 4 | 7 | 1 | 2 | 9 | |||||||
| 5 | 3 | 5 | 8 | 4 | |||||||
| 6 | 2 | 4 | 9 | 3 | |||||||
| 7 | 9 | 5 | 6 | 2 | |||||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | ||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 8 | Step 1: #6 is in Rows 1 & 2: #6 MUST go in Cell I3… | |||||||
| 2 | 6 | 3 | 4 | 8 | 7 | 5 | |||||
| 3 | 5 | 2 | 7 | 9 | 4 | 6 | |||||
| 4 | 7 | 1 | 4 | 2 | 9 | Step 2: #4 is in Rows 5 & 6: #4 MUST go in Cell D4 | |||||
| 5 | 3 | 5 | 8 | 4 | (cf #4 in Column F @ F8 excludes use of Cell F4) | ||||||
| 6 | 2 | 4 | 9 | 3 | |||||||
| 7 | 9 | 5 | 6 | 2 | |||||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | ||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 8 | Step 3: #8 is in Rows 1 & 2: #8 MUST go in Cell B3… | |||||||
| 2 | 6 | 3 | 4 | 8 | 7 | 5 | |||||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | ||||
| 4 | 7 | 1 | 4 | 2 | 3 | 9 | Step 4: #3 is in Rows 5 & 6: #3 MUST go in Cell F4… | ||||
| 5 | 3 | 5 | 8 | 4 | |||||||
| 6 | 2 | 4 | 9 | 3 | |||||||
| 7 | 9 | 5 | 6 | 2 | |||||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | ||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 8 | Step 5: Complete Column F: #1 MUST go in Cell F7… | |||||||
| 2 | 6 | 3 | 4 | 8 | 7 | 5 | |||||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | Step 6: #3 is in Columns G & I: #3 MUST go in Cell H7… | |||
| 4 | 7 | 1 | 4 | 2 | 3 | 9 | |||||
| 5 | 3 | 5 | 8 | 4 | |||||||
| 6 | 2 | 4 | 9 | 3 | |||||||
| 7 | 9 | 5 | 6 | 1 | 3 | 2 | |||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | ||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 8 | Step 7: #8 is in Columns B & C: #8 MUST go in Cell A4 | |||||||
| 2 | 6 | 3 | 4 | 8 | 7 | 5 | (cf #8 in Row 5 @ H5 excludes use of Cell A5) | ||||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | ||||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 9 | ||||
| 5 | 3 | 5 | 8 | 4 | |||||||
| 6 | 2 | 4 | 9 | 3 | |||||||
| 7 | 9 | 5 | 6 | 1 | 3 | 2 | |||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | ||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 8 | Step 8: Complete Row 4: need #s 5 & 6… | |||||||
| 2 | 6 | 3 | 4 | 8 | 7 | 5 | #6 can't go in Cell G4 (cf #6 in Column G @ G9), so | ||||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | #6 MUST go in Cell H4, & therefore #5 MUST go in Cell G4 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 3 | 5 | 8 | 4 | Step 9: Now #5 is in Rows 4 & 5: #5 MUST go in Cell B6… | ||||||
| 6 | 2 | 5 | 4 | 9 | 3 | ||||||
| 7 | 9 | 5 | 6 | 1 | 3 | 2 | |||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | ||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 2 | 8 | Step 10: Complete Column H: need #s 1 & 2… | ||||||
| 2 | 6 | 3 | 4 | 8 | 7 | 5 | #2 can't go in Cell H6 (cf #2 in Row 6 @ A6), so | ||||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | #2 MUST go in Cell H1, & therefore #1 MUST go in Cell H6 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 3 | 5 | 8 | 4 | |||||||
| 6 | 2 | 5 | 4 | 9 | 1 | 3 | |||||
| 7 | 9 | 5 | 6 | 1 | 3 | 2 | |||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | ||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 2 | 8 | Step 11: Complete Block CC: #1 MUST go in Cell G2… | ||||||
| 2 | 6 | 3 | 4 | 8 | 1 | 7 | 5 | ||||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | ||||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | Step 12: Complete Block FF: need #s 2 & 7… | |
| 5 | 3 | 5 | 2 | 8 | 4 | #2 can't go in Cell G6 (cf #2 in Row 6 @ A6), so | |||||
| 6 | 2 | 5 | 4 | 9 | 7 | 1 | 3 | #2 MUST go in Cell G5, & therefore #7 MUST go in Cell G6 | |||
| 7 | 9 | 5 | 6 | 1 | 3 | 2 | |||||
| 8 | 5 | 4 | 9 | 1 | Step 13: Now #7 is in Columns G & H: #7 MUST go in Cell I9 | ||||||
| 9 | 1 | 8 | 2 | 6 | 5 | 7 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 2 | 8 | Step 14: Complete Row 2: need #s 2 & 9… | ||||||
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | #2 can't go in Cell A2 (cf #2 in Column A @ A6), so | |
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | #2 MUST go in Cell D2, & therefore #9 MUST go in Cell A2 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 3 | 9 | 5 | 2 | 8 | 4 | Step 15: Now #9 is in Columns A & B: #9 MUST go in Cell C5 | ||||
| 6 | 2 | 5 | 4 | 9 | 7 | 1 | 3 | ||||
| 7 | 9 | 5 | 6 | 1 | 3 | 2 | |||||
| 8 | 5 | 4 | 9 | 1 | |||||||
| 9 | 1 | 8 | 2 | 6 | 5 | 7 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 6 | 3 | 2 | 8 | Step 16: Complete Block DD: #6 MUST go in Cell A5… | ||||||
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | ||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | Step 17: Now #6 is in Columns A & B: #6 MUST go in Cell C8 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 6 | 3 | 9 | 5 | 2 | 8 | 4 | Step 18: Complete Block II: need #s 4 & 8… | |||
| 6 | 2 | 5 | 4 | 9 | 7 | 1 | 3 | #4 can't go in Cell G8 (cf #4 in Row 8 @ F8), so | |||
| 7 | 9 | 5 | 6 | 1 | 4 | 3 | 2 | #4 MUST go in Cell G7, & therefore #8 MUST go in Cell G8 | |||
| 8 | 6 | 5 | 4 | 8 | 9 | 1 | |||||
| 9 | 1 | 8 | 2 | 6 | 5 | 7 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 7 | 6 | 3 | 2 | 8 | Step 19: Complete Row 7: need #s 7 & 8… | |||||
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | #8 can't go in Cell A7 (cf #8 in Column A @ A4), so | |
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | #8 MUST go in Cell D7, & therefore #7 MUST go in Cell A7 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 6 | 3 | 9 | 5 | 2 | 8 | 4 | Step 20: Now #7 is in Columns A & B: #7 MUST go in Cell C1 | |||
| 6 | 2 | 5 | 4 | 9 | 7 | 1 | 3 | ||||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 6 | 5 | 4 | 8 | 9 | 1 | |||||
| 9 | 1 | 8 | 2 | 6 | 5 | 7 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 7 | 6 | 3 | 2 | 8 | Step 21: Complete Row 6: need #s 6 & 8… | |||||
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | #6 can't go in Cell E6 (cf #6 in Column E @ E7), so | |
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | #6 MUST go in Cell D6, & therefore #8 MUST go in Cell E6 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 6 | 3 | 9 | 5 | 2 | 8 | 4 | ||||
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | ||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 6 | 5 | 4 | 8 | 9 | 1 | |||||
| 9 | 1 | 8 | 2 | 6 | 5 | 7 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 4 | 1 | 7 | 6 | 3 | 2 | 8 | Step 22: Complete Block AA: need #s 1 & 4… | |||
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | #1 can't go in Cell A1 (cf #1 in Column A @ A9), so | |
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | #1 MUST go in Cell B1, & therefore #4 MUST go in Cell A1 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 6 | 3 | 9 | 5 | 2 | 8 | 4 | ||||
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | ||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 6 | 5 | 4 | 8 | 9 | 1 | |||||
| 9 | 1 | 8 | 2 | 6 | 5 | 7 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 4 | 1 | 7 | 5 | 9 | 6 | 3 | 2 | 8 | Step 23: Complete Row 1: need #s 5 & 9… | |
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | #5 can't go in Cell E1 (cf #5 in Column # @ E8), so | |
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | #5 MUST go in Cell D1, & therefore #9 MUST go in Cell E1 | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 6 | 3 | 9 | 5 | 2 | 8 | 4 | ||||
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | ||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 6 | 5 | 4 | 8 | 9 | 1 | |||||
| 9 | 1 | 8 | 2 | 6 | 5 | 7 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 4 | 1 | 7 | 5 | 9 | 6 | 3 | 2 | 8 | Step 24: Complete Column A: #3 MUST go in Cell A8… | |
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | ||
| 3 | 5 | 8 | 2 | 7 | 9 | 4 | 6 | Step 25: Complete Column B: need #s 2 & 4… | |||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | #4 can't go in Cell B8 (cf #4 in Row 8 @ F8), so | |
| 5 | 6 | 3 | 9 | 5 | 2 | 8 | 4 | #4 MUST go in Cell B9, & therefore #2 MUST go in Cell B8 | |||
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | ||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 3 | 2 | 6 | 5 | 4 | 8 | 9 | 1 | |||
| 9 | 1 | 4 | 8 | 2 | 6 | 5 | 7 | ||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 4 | 1 | 7 | 5 | 9 | 6 | 3 | 2 | 8 | Step 26: Complete Row 9: need #s 3 & 9… | |
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | #9 can't go in Cell E9 (cf #9 in Column E @ E1), so | |
| 3 | 5 | 8 | 2 | 3 | 7 | 9 | 4 | 6 | #9 MUST go in Cell D9, & therefore #3 MUST go in Cell E9 | ||
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 6 | 3 | 9 | 5 | 2 | 8 | 4 | Step 27: #3 is now in Columns E & F: #3 MUST go in Cell D3 | |||
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | ||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 3 | 2 | 6 | 5 | 4 | 8 | 9 | 1 | |||
| 9 | 1 | 4 | 8 | 9 | 3 | 2 | 6 | 5 | 7 | ||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 4 | 1 | 7 | 5 | 9 | 6 | 3 | 2 | 8 | Step 28: Complete Block BB: #1 MUST go in Cell E3… | |
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | ||
| 3 | 5 | 8 | 2 | 3 | 1 | 7 | 9 | 4 | 6 | Step 29: #1 is now in Columns E & F: #1 MUST go in Cell D5 | |
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | ||
| 5 | 6 | 3 | 9 | 1 | 5 | 2 | 8 | 4 | |||
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | ||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 3 | 2 | 6 | 5 | 4 | 8 | 9 | 1 | |||
| 9 | 1 | 4 | 8 | 9 | 3 | 2 | 6 | 5 | 7 | ||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 4 | 1 | 7 | 5 | 9 | 6 | 3 | 2 | 8 | Step 30: Complete Block EE: #7 MUST go in Cell E5… | |
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | ||
| 3 | 5 | 8 | 2 | 3 | 1 | 7 | 9 | 4 | 6 | Step 31: Complete Block HH (& Puzzle): | |
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | #7 MUST go in Cell D8. | |
| 5 | 6 | 3 | 9 | 1 | 7 | 5 | 2 | 8 | 4 | ||
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | ||
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | ||
| 8 | 3 | 2 | 6 | 7 | 5 | 4 | 8 | 9 | 1 | ||
| 9 | 1 | 4 | 8 | 9 | 3 | 2 | 6 | 5 | 7 | ||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 4 | 1 | 7 | 5 | 9 | 6 | 3 | 2 | 8 | 45 | Final Proof: |
| 2 | 9 | 6 | 3 | 2 | 4 | 8 | 1 | 7 | 5 | 45 | - All Rows add up to 45; |
| 3 | 5 | 8 | 2 | 3 | 1 | 7 | 9 | 4 | 6 | 45 | |
| 4 | 8 | 7 | 1 | 4 | 2 | 3 | 5 | 6 | 9 | 45 | |
| 5 | 6 | 3 | 9 | 1 | 7 | 5 | 2 | 8 | 4 | 45 | |
| 6 | 2 | 5 | 4 | 6 | 8 | 9 | 7 | 1 | 3 | 45 | |
| 7 | 7 | 9 | 5 | 8 | 6 | 1 | 4 | 3 | 2 | 45 | |
| 8 | 3 | 2 | 6 | 7 | 5 | 4 | 8 | 9 | 1 | 45 | |
| 9 | 1 | 4 | 8 | 9 | 3 | 2 | 6 | 5 | 7 | 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 | |||||||||
Send your Comments to joe-ks.com