This puzzle is essentially a Latin square with addition. All you really need to know is how to add single-digit numbers, although subtraction is also useful. Once you’ve spend a few minutes sorting out which numbers mean what, you’re ready to start puzzling!
Can you figure out the rules from this solved puzzle?
Getting started Classroom demonstration 4x4 puzzles (and solutions , just in case) 5x5 puzzles (and solutions ) 6x6 puzzles (and solutions ) Puzzles in three sizes Once you’ve mastered these, you might enjoy creating your own puzzles: just start with the tick and X-marks, work out the sums, then decide how many of the sums to give as clues.