MathDB

3

Part of 1971 Kurschak Competition

Problems(1)

30 boxes each with a unique key.

Source: 1971 Hungary - Kürschák Competition p3

10/15/2022
There are 3030 boxes each with a unique key. The keys are randomly arranged in the boxes, so that each box contains just one key and the boxes are locked. Two boxes are broken open, thus releasing two keys. What is the probability that the remaining boxes can be opened without forcing them?
combinatorics