24 (puzzle)

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "24" puzzle – news · newspapers · books · scholar · JSTOR (December 2015) (Learn how and when to remove this message)

The 24 puzzle is an arithmetical puzzle in which the objective is to find a way to manipulate four integers so that the end result is 24. For example, for the numbers 4, 7, 8, 8, a possible solution is ${\displaystyle (7-(8\div 8))\times 4=24}$. Note that all four numbers must be used exactly once.

The problem has been played as a card game in Shanghai since the 1960s,^[1] using playing cards. It has been known by other names, including Maths24.^{[citation needed]} A proprietary version of the game has been created which extends the concept of the basic game to more complex mathematical operations.