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# S1 permutations +combinations qus watch

1. heya - i came across this question and it seems to be easy at first glance but i can't seem to figure out how to do it:

the letters of the word POSSESSES are written on 9 cards, one on each card. The careds are shuffled and 4 of them are selected and arranged in a straight line.

a) How many possible selections are there of 4 letters? (12)
b) How many arrangements are there of 4 letters? (115)

i would have thought it's something like 9c4 / 5! 2! for (a) and
9!/5! 2! and then choose 4 from the answer for (b)
but they're both completely wrong!

would really really appreciate it if someone could help me out with the method of solving this!

thanxxxxxxxxx!
2. (Original post by nervous)
would really really appreciate it if someone could help me out with the method of solving this!

thanxxxxxxxxx!
I totally agree with that!! just this and this = this doesn't help but thats all I get from people at college!

Is there a method for questions like this?
3. Num of 'S's in the 4 cards => Num of selections : Num of arrangements
0 => 1 (EEOP) : 12
1 => 3 (S with one of EEO, EEP, EOP) : 48 (= 12 + 12 + 24)
2 => 4 (SS with one of EE, EO, EP, OP) : 42 (= 6 + 12 + 12 + 12)
3 => 3 (SSS with one of E, O, P) : 12 (= 4 + 4 + 4)
4 => 1 (SSSS) : 1
---------------------------------
Total => 12 : 115
4. YAY!! thanx sooo much Jonny W! - really appreciate it!!
5. Are Permutation and Combinations in S1 ????
6. yup S1 does have permutations and combinations
anyway - had my stats paper yesterday and it was soooo tricky! and the permutations and combinations qus had smth to do with this menu and they had this fine print at the bottom that said "each main course comes with either potato or salad" ! and like 1 person saw it out of the 18 of us!
i was soo upset cos that was an easy question too!

guess it was my fault huh for not reading the question fully?
oh well
anyway - my advice to all of u is to look everywhere before answering the question!! - u probably do that anyway but... yea...

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