Question 1: The total number of different combinations of these letters can be made from letters of the word 'MISSISSIPPI"?
Question 2: How many different words can be formed with the letters of the word 'MISSISSIPPI'?
My question: What is the difference between above two questions which would then help me understand how to calculate the answers?
I understand question 1 involves selecting from set of alike and different objects and question 2 involves group. I want to understand why.
A combination refers to the selection of a subset of the elements in some specified collection, usually a set. In this case, you are selecting a subset of a multiset since some of the letters in MISSISSIPPI are repeated. In a combination, what matters are which objects are selected, not the order in which they are selected.
A word is a sequence of characters from some specified alphabet. The order of the letters in the string matters, so IMSS is considered to be different from MISS.