math- panting a room question

[joonkimdds]

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there are 5 rooms and a painter has 8 colors. The rooms are A,B,C,D, and E.
How many different ways can he paint the room?

the solution says 8*7*6*5*4=6720

But I think it should be 8*8*8*8*8= 32768

let's say one of the 8 colors is blue.
can't we paint all 5 rooms with blue?
if we use 8*7*6*5*4=6720 method, that is like saying that
we are spending all the blue color paint in one room and there is not
enough blue color to paint the other rooms.
without knowing how much paint we have, i think this question is unclear.

can someone explain to me whether i am right or wrong?

 

[doc3232]

After you use your first color you can not use it again.
So you have to multiply by the previous number minus one.
Hope that helps.

 

[nixon13]

I think you would just use 8!/(8-5)!

8x7x6x5x4x3x2x1/3x2x1 = 8x7x6x5x4 = 6720.

Is that correct?

 

[Ghettob1aster]

It is an unclear question. It does not give you any restrictions on how many rooms you can paint with just one color. If there are any like this on the exam, just go with it.

 

[vvvv]

It is an unclear question. It does not give you any restrictions on how many rooms you can paint with just one color. If there are any like this on the exam, just go with it.

I post this qeustion couple days ago. I agree it is unclear question and I think there are alot of unclear questions in Destroyer.

 

[Hugh Mannity]

After you use your first color you can not use it again.
So you have to multiply by the previous number minus one.
Hope that helps.

That was the point of the OP, he was saying that it never said you couldn't use it again. I think he obviously knows the formula but was unclear about the logic of the question, which is, unfortunately, BS in many questions DAT related.