Medium Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 10: Six Medium (DiffLev 7-8) tpsmith Puzzles (numbers 79-84) 
 
-  Step-by-step instructions for solving  Puzzle 79, (78/144)   Diff: 7/999.9963
 -  Step-by-step instructions for solving  Puzzle 80, (89/144)   Diff: 7/999.9995
 -  Step-by-step instructions for solving  Puzzle 81, (85/144)   Diff: 8/9999.9983
 -  Step-by-step instructions for solving  Puzzle 82, (85/144)   Diff: 8/9998.6599
 -  Step-by-step instructions for solving  Puzzle 83, (90/144)   Diff: 8/9999.9974
 -  Step-by-step instructions for solving  Puzzle 84, (90/144)   Diff: 8/9799.9992