If X and Y are two sets such that X `uu`Y has 50 elements, X has 28 elements and Y has 32 elements, how many elements does X `nn`Y have?

Explanation

To solve the problem, we need to find the number of elements in the intersection of sets X and Y, denoted as \( n(X \cap Y) \). We are given the following information:

- The number of elements in the union of sets X and Y: \( n(X \cup Y) = 50 \)
- The number of elements in set X: \( n(X) = 28 \)
- The number of elements in set Y: \( n(Y) = 32 \)

We can use the formula for the union of two sets:

...