
| Easy Puzzle #25 - 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 | 1 | 9 | 3 | 6 | 4 | Easy Puzzle #25 - October 25, 2005 © joe-ks.com | |||||
| 2 | 3 | 4 | 7 | 1 | One possible Solution Method follows below… | ||||||
| 3 | 1 | 9 | 4 | ||||||||
| 4 | 6 | 3 | 4 | ||||||||
| 5 | 9 | 4 | 5 | 1 | 7 | ||||||
| 6 | 7 | 8 | 9 | 2 | |||||||
| 7 | 5 | 7 | 3 | ||||||||
| 8 | 2 | 7 | 8 | 9 | 6 | ||||||
| 9 | 8 | 6 | 1 | ||||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 3 | 6 | 4 | Step 1: #9 is in Rows 1 & 2: #9 MUST go in Cell G2… | |||||
| 2 | 3 | 4 | 9 | 7 | 1 | ||||||
| 3 | 1 | 9 | 4 | ||||||||
| 4 | 6 | 3 | 4 | Step 2: #4 is in Rows 4 & 5: #4 MUST go in Cell D6… | |||||||
| 5 | 9 | 4 | 5 | 1 | 7 | ||||||
| 6 | 7 | 4 | 8 | 9 | 2 | ||||||
| 7 | 5 | 7 | 3 | Step 3: #7 is in Rows 7 & 8: #7 MUST go in Cell G9 | |||||||
| 8 | 2 | 7 | 8 | 9 | 6 | (cf #7 in Column I @ I5 excludes use of Cell I9) | |||||
| 9 | 8 | 6 | 7 | 1 | |||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 3 | 6 | 4 | Step 4: #9 is in Columns A & C: #9 MUST go in Cell B7… | |||||
| 2 | 3 | 4 | 9 | 7 | 1 | ||||||
| 3 | 1 | 9 | 4 | ||||||||
| 4 | 6 | 3 | 4 | 9 | Step 5: #4 is in Columns D & F: #4 MUST go in Cell E8… | ||||||
| 5 | 9 | 4 | 5 | 1 | 7 | ||||||
| 6 | 7 | 4 | 8 | 9 | 2 | ||||||
| 7 | 9 | 5 | 7 | 3 | Step 6: #9 is in Columns G & H: #9 MUST go in Cell I4 | ||||||
| 8 | 2 | 7 | 8 | 4 | 9 | 6 | (cf #9 in Row 6 @ F6 excludes use of Cell I6) | ||||
| 9 | 8 | 6 | 7 | 1 | |||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 3 | 6 | 4 | Step 7: Complete Column E: need #s 1 & 2… | |||||
| 2 | 3 | 4 | 2 | 9 | 7 | 1 | #1 can't go in Cell E2 (cf #1 in Row 2 @ I2), so | ||||
| 3 | 1 | 9 | 4 | #1 MUST go in Cell E4, & therefore #2 MUST go in Cell E2 | |||||||
| 4 | 6 | 3 | 1 | 4 | 9 | ||||||
| 5 | 9 | 4 | 5 | 1 | 7 | ||||||
| 6 | 7 | 4 | 8 | 9 | 2 | ||||||
| 7 | 9 | 5 | 7 | 3 | |||||||
| 8 | 2 | 7 | 8 | 4 | 9 | 6 | |||||
| 9 | 8 | 6 | 7 | 1 | |||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 3 | 6 | 4 | Step 8: #1 is in Columns D & E: #1 MUST go in Cell F8 | |||||
| 2 | 3 | 4 | 2 | 9 | 7 | 1 | (cf #1 in Row 9 @ H9 excludes use of Cell F9) | ||||
| 3 | 1 | 9 | 4 | ||||||||
| 4 | 6 | 3 | 1 | 4 | 9 | ||||||
| 5 | 9 | 4 | 5 | 1 | 7 | ||||||
| 6 | 7 | 4 | 8 | 9 | 2 | ||||||
| 7 | 9 | 5 | 7 | 3 | |||||||
| 8 | 2 | 7 | 8 | 4 | 1 | 9 | 6 | ||||
| 9 | 8 | 6 | 7 | 1 | |||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 3 | 6 | 4 | Step 9: Complete Block HH: need #s 2 & 9… | |||||
| 2 | 3 | 4 | 2 | 9 | 7 | 1 | #9 can't go in Cell F9 (cf #9 in Column F @ F6), so | ||||
| 3 | 1 | 9 | 4 | #9 MUST go in Cell D9, & therefore #2 MUST go in Cell F9 | |||||||
| 4 | 6 | 3 | 1 | 4 | 9 | ||||||
| 5 | 9 | 4 | 2 | 5 | 1 | 7 | Step 10: Now #2 is in Columns E & F: #2 MUST go in Cell D5 | ||||
| 6 | 7 | 4 | 8 | 9 | 2 | ||||||
| 7 | 9 | 5 | 7 | 3 | |||||||
| 8 | 2 | 7 | 8 | 4 | 1 | 9 | 6 | ||||
| 9 | 8 | 9 | 6 | 2 | 7 | 1 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 7 | 3 | 6 | 4 | Step 11: Complete Block EE: need #s 6 & 7… | ||||
| 2 | 3 | 4 | 2 | 9 | 7 | 1 | #6 can't go in Cell F4 (cf #6 in Row 4 @ C4), so | ||||
| 3 | 1 | 9 | 4 | #6 MUST go in Cell F5, & therefore #7 MUST go in Cell F4 | |||||||
| 4 | 6 | 3 | 1 | 7 | 4 | 9 | |||||
| 5 | 9 | 4 | 2 | 5 | 6 | 1 | 7 | Step 12: Now #7 is in Columns E & F: #7 MUST go in Cell D1 | |||
| 6 | 7 | 4 | 8 | 9 | 2 | (cf #7 in Row 2 @ H2 excludes use of Cell D2) | |||||
| 7 | 9 | 5 | 7 | 3 | |||||||
| 8 | 2 | 7 | 8 | 4 | 1 | 9 | 6 | ||||
| 9 | 8 | 9 | 6 | 2 | 7 | 1 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 7 | 3 | 6 | 4 | Step 13: Complete Column D: #6 MUST go in Cell D2… | ||||
| 2 | 3 | 4 | 6 | 2 | 9 | 7 | 1 | ||||
| 3 | 1 | 9 | 4 | ||||||||
| 4 | 6 | 3 | 1 | 7 | 4 | 9 | Step 14: Complete Row 5: need #s 3 & 8… | ||||
| 5 | 9 | 3 | 4 | 2 | 5 | 6 | 1 | 8 | 7 | #8 can't go in Cell B5 (cf #8 in Column B @ B9), so | |
| 6 | 7 | 4 | 8 | 9 | 2 | #8 MUST go in Cell H5, & therefore #3 MUST go in Cell B5 | |||||
| 7 | 9 | 5 | 7 | 3 | |||||||
| 8 | 2 | 7 | 8 | 4 | 1 | 9 | 6 | ||||
| 9 | 8 | 9 | 6 | 2 | 7 | 1 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 7 | 3 | 6 | 4 | Step 15: Row 4 needs #8: #8 MUST go in Cell A4 | ||||
| 2 | 3 | 4 | 6 | 2 | 9 | 7 | 1 | (cf #8 in Column B @ B9 excludes use of Cell B4, & | |||
| 3 | 7 | 1 | 9 | 4 | #8 in Column H @ H5 excludes use of Cell H4) | ||||||
| 4 | 8 | 6 | 3 | 1 | 7 | 4 | 9 | ||||
| 5 | 9 | 3 | 4 | 2 | 5 | 6 | 1 | 8 | 7 | Step 16: #7 is in Rows 1 & 2: #7 MUST go in Cell A3 | |
| 6 | 7 | 4 | 8 | 9 | 2 | (#7 in Column B @ B8 excludes use of Cell B3, & | |||||
| 7 | 9 | 5 | 7 | 3 | #7 in Column C @ C6 excludes use of Cell C3) | ||||||
| 8 | 2 | 7 | 8 | 4 | 1 | 9 | 6 | ||||
| 9 | 8 | 9 | 6 | 2 | 7 | 1 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 1 | 9 | 7 | 3 | 6 | 4 | Step 17: Block DD needs #1: #1 MUST go in Cell A6 | ||||
| 2 | 3 | 4 | 6 | 2 | 9 | 7 | 1 | (cf #1 in Column B @ B1 excludes use of Cells B4 & B6) | |||
| 3 | 7 | 1 | 9 | 4 | |||||||
| 4 | 8 | 6 | |||||||||