Question

. In how many different ways can we partition an n-element set into two parts if one part has four elements and the other part has all the remaining elements

Answer 1

Answer:

The answer is "$\bold{\begin{pmatrix}n \\4\end{pmatrix}}$".

Step-by-step explanation:

There are total $\begin{pmatrix}n \\4\end{pmatrix}$possibilities, in which the given situation will be handle.      

In the given problem, it can be considered as choosing 4 numbers or the subset of 4 elements from the original set, in which it is necessary for the partition is given in each subset of 4 elements.