Subtest 3
Latin squares
A 5×5 square of A–E. Each letter once per row and column. Name the highlighted cell.
The definition is the whole syllabus
A Latin square of order 5 is a grid in which each of five symbols appears once in every row and once in every column. Sudoku without boxes. You are not asked to finish the square — only the marked cell — but harder items require filling a neighbour first.
Elimination, then a forced cell
List the letters missing from the target’s row. Cross out any that already appear in its column. If one letter remains, you are done. If two remain, find a row or column elsewhere that is only missing one letter, fill it, and return. Do not guess early on a hard grid; the unique answer is always determined.
Pencil marks
On paper you would write small candidates. On the official digital client you work mentally or on the provided scrap. Here you can tap a cell to try a letter in practice mode; the mock hides that crutch.