HERE’S HOW IT WORKS: To solve Numbrix, PARADE’s puzzle by Marilyn vos Savant, you must complete a number matrix using logic and memory. No math or guesswork involved! Just fill in the puzzle so the consecutive numbers from 1 to 81 follow a horizontal or vertical path (no diagonals). Each puzzle has a unique solution, and difficulty varies from easy (vanilla) to extra-challenging (blueberry).