For instance both permutations and combinations are collections of objects. In our example the order of the digits were important if the order didnt matter we would have what is the definition of a combination. This is particularly true in probability when examining the formula for combinations.
A combination is a mathematical technique that determines the number of possible arrangements in a collection of items where the order of the selection does not matter.
Times k the number of chairs or spots 4 in the video. Times k the number of chairs or spots 4 in the video. Combinations are the various ways in which objects from a given set may be selected. So in Mathematics we use more.