Derangement Puzzles: How to Count Mix-Ups With Nothing in Place
How to count and solve derangement puzzles where no jar, key or tile may stay in its own place, with the counting rule, a table and a clue puzzle.
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Counting and Combination Puzzles: How to Count Every Way
Learn when to multiply and when to add, how to count orderings, groups and number splits, and how to avoid double counting, with a worked puzzle.
Arithmetic Progression Puzzles: Keep Numbers Unevenly Spaced
Pick as many numbers as you can with no three evenly spaced. The midpoint test, greedy pass and doubling trick, with worked examples and practice.
Number Sequence Puzzles: How to Find What Comes Next
Check the gaps, then the gaps between gaps, then the sum of the two previous terms. Worked number sequence puzzles, no-repeat strings and practice.
How to Solve House and Neighbour Logic Puzzles
Turn left, right and next-to clues into tiles on a strip of houses, test the few places each can sit, and finish with one row. Worked example and practice.
Process of Elimination in Puzzles: Rule Out Until One Is Left
How to use the process of elimination in puzzles: list options, cross out what fails, and add a guess-and-check step when you stall. Worked grids.
Knights, Knaves and Normals: Three-Type Logic Puzzles
Knights, knaves and normals puzzles with a truth-teller, a liar and a normal who can say either: a case method, a worked example and a practice puzzle.
Self-Referential Puzzles: How to Solve Statements About Themselves
Test every scenario and keep the one where each statement matches its own truth: liar claims, counting lists, self-counting sentences and sequences.
How to Solve Scheduling Puzzles: Orders, Rounds and Clashes
Turn each clue into a before, after or same-round rule, fix the ends first and fill the rest. A worked ordering puzzle and a round schedule to practise.
Seating Arrangement Puzzles: How to Solve Round and Row Tables
Fix one seat, place locked pairs, split into cases and test each clue. A worked round-table puzzle, the own-seat rule and a practice puzzle with answer.
Hat Colour Puzzles: How to Reason From What Others See
Solve hat colour puzzles by listing every pattern and striking out what each answer rules out. A worked example, the classic game and a practice puzzle.
How to Solve Boat-Placement Puzzles: Find Every Hidden Boat
Use row and column counts and the no-touching rule to find every hidden boat. A clear method, a worked six by six puzzle and a practice grid.
How to Solve Pair-Matching Path Puzzles: Join Every Pair
Join equal numbers with paths that never cross and fill every cell. Learn corner and edge forcing, then try a worked puzzle and a practice grid.
How to Solve Star-Placement Puzzles: Stars That Never Touch
Place stars in every row, column and region so that none touch, even at corners. Five core moves, a worked five by five puzzle and a practice grid.
How to Solve Building Height Puzzles: Count What You Can See
Read edge clues as visible buildings, use the tallest-at-the-edge and cap rules, then follow a worked four by four building height puzzle and a practice grid.
How to Solve Sum Grid Puzzles: Runs, Totals and Digit Sets
Learn the totals that allow only one set of digits, use crossing runs and the no-repeat rule, then follow a worked sum grid puzzle and try a practice grid.
Calculation Cage Puzzles: How to Solve Target-and-Operation Grids
Start with single cells and one-pair cages, list digit sets for sums and products, then use rows and columns. A worked grid and a practice puzzle.
How to Solve Loop Puzzles: The Inside and Outside Method
Draw one closed loop by the numbers. Label cells inside or outside, use zeros, corners and the dot rule, then try a worked and a practice puzzle.
Inequality Number Puzzles: How to Solve Greater-Than Grids
Use each sign to strike out digits, follow chains and valleys, and finish with row and column scans. A full worked grid and a practice puzzle.
How to Solve Latin Square Puzzles: Two Moves and a Worked Grid
Fill each row and column with every symbol once. Learn the only-candidate and only-place moves, a full worked grid and a practice puzzle.