Permutations & Combinations

[RahulSharma]

I'm sorry cattie, but ur answers are incorrect.

Take some examples to verify yourself.

p^n may not be always divisible by n!. This simple thing you would agree to!

[cattie]

Oops! I'm sorry for that. I guess the 1/n! part shouldn't have been included as if that is done it should also be multiplied by n! once again which would lead it to p^n. sorry for that but now it seems to be right.
anyways could u point out the logical mistake in it keeping the mathematical part apart(anyways now it seems to be right).
ans to (1)----------p^n

[RahulSharma]

The answer is right if the objects and people are distinct.

[couger]

hi ghulam,
personally i feel that i am not confortable in PC as in other topics..
can u give me some suggestion where in i can imporve my PC...

[cattie]

The ppl r obviously distinct but the objs needn't be or rather shouldn't be distinct as is the prob statement.
That is why the 1/n! appears to out ride the n! in the numerator. If the objs had been distinct then the ans would have been (p^n)*n!

[RahulSharma]

Suggested reading for P&C.

Tata McGraw Hill Mathematics for JEE. Read this line by line, your P&C will be crystal clear. CAT(original) 2003 Quant on P&C had 2 questions from here

Cattie u are a bit confused with this, please verify yourself with the help of examples.