Problem

2010 AIME II Problem 8

Let N be the number of ordered pairs of nonempty sets \mathcal{A} and \mathcal{B} that have the following properties:

- \mathcal{A} \cup \mathcal{B} = \{1,2,3,4,5,6,7,8,9,10,11,12\},

- \mathcal{A} \cap \mathcal{B} = \emptyset,

- The number of elements of \mathcal{A} is not an element of \mathcal{A},

- The number of elements of \mathcal{B} is not an element of \mathcal{B}.

Find N.

Leading zeroes must be inputted, so if your answer is 34, then input 034


Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.


Show/Hide Problem Tags

Problem Tags: Counting and probability

Want to contribute problems and receive full credit? Click here to add your problem!
Please report any issues to us in our Discord server
Go to previous contest problem (SHIFT + Left Arrow) Go to next contest problem (SHIFT + Right Arrow)