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Perms/Combs (1 Viewer)

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5 travellers arrive at a town that has 3 hotels. Two of the travellers, Joanne and David, wish to stay in the same hotel. In how many ways can the 5 travellers occupy the hotels, if each hotel must be occupied by at least 1 person?
 

thongetsu

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Tim likes male genitals.

Perms and combs suck ass. >:|
 

thongetsu

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Also it was in an exam so we dunno the answer
 

11MX11

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It is given that 3 hotels must be occupied.
Since Joanne and David are always staying together they are to be counted as 1 unit. There are three other ppl left, so together there are 4units.

so in nPr, n=4 and r=3.

Then the number of possibilities is 4P3.

However, there are 4 units and 3 hotels, this means that 1 unit will be left out and must stay in another hotel that is occupied. For this 1 unit there are 3 possibilities, which are the hotels.

So the total possibilities are 4P3 x 3 = 72.

correct me if im wrong.
 

thongetsu

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Tim wishes he had Jennifer in the ass.

Or maybe he did. Eeeewwww.
 

thongetsu

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Tim uses maths equations as a stimulus for "fapping".

Also, what'd you get for the Q
cos^-1*8/17 = A
Find tan2A
or seomthing lyk dat.
 

hscishard

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It is given that 3 hotels must be occupied.
Since Joanne and David are always staying together they are to be counted as 1 unit. There are three other ppl left, so together there are 4units.

so in nPr, n=4 and r=3.

Then the number of possibilities is 4P3.

However, there are 4 units and 3 hotels, this means that 1 unit will be left out and must stay in another hotel that is occupied. For this 1 unit there are 3 possibilities, which are the hotels.

So the total possibilities are 4P3 x 3 = 72.

correct me if im wrong.
Or
(2! x 3x2 x 1!)3!
2! Since the two people is fixed in 1 hotel.
3x2 for the second hotel
1 for the remaining.
This can be done in 3! because of 3 hotels.
=72
 

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