The letters of the word POSSESSES are written on 9 cards, one on each card. The cards are shuffled and four of them are selected and arranged in a straight line.
(a) how many possible selections are there of 4 letters?
(b"how many arrangements are there of 4 letters?
The Attempt at a Solution
Well first of all, how do you start of a question like this. for the first part(a)
9C4=126 but here i see there are 5 s's and 2 e's. how can i apply the formula to this question. because there are 5 s's and 2e's so this forumla is invalid.
for arrangements for 9 words. 9!/5!2! but this is for the 9 letters. i am only focusing on the four words being selected. how can i start