What is the difference between these questions?

[goelmohit2002]

Hi All,

Can someone please tell what is the difference between the following two questions and how to arrive at the answers of each ?

Q1) Six alphabets P,Q,R,S,T and U have to be arranged in six numbered positions(1-6). How many ways can you arrange them so that P is not in position numbered 3, Q is not in position numbered 5 and R is not in position numbered 6.
a) 714
b) 426
c) 240
d) 120
e) 252
OA = A.

Q2) Six alphabets P,Q,R,S,T and U have to be arranged in six numbered positions(1-6). How many ways can you arrange them so that neither P is in position numbered 3, nor Q is in position numbered 5 and nor R is in position numbered 6.
a) 714
b) 426
c) 240
d) 120
e) 252
OA = B.

[RonPurewal]

wow. whatever source you got these from - set it on fire, run away as fast as you can, and don't look back.

the first question is just plain wrong.
the wording, as written, would mean that none of those letters is in the named slot.
that's not the problem they solved, though. 714 would be 720 (= 6!) minus 6 (= 3!). this is the number of combinations in which not all of the letters are in the named slots - i.e., it's ok for 1 or 2 of them to be in the named slots, but not all three. (hence 6! for all possible arrangements, minus 3! for the arrangements that are possible with those three letters fixed in place).

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the second question has wording that is so awkward that it's nearly meaningless. if it does mean something, though, it should mean exactly the same thing as the first wording.

as far as i can tell, it's impossible to do this problem without an absolutely ridiculous number of steps, as well as the inclusion-exclusion principle for 3 items (which is not required on the gmat). this problem is therefore completely irrelevant to the gmat.