Probability question!!!

[pandalove89]

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Jill has six different books. She will select one book on Monday and a different one to read on Wednesday. In how many ways can Jill select two different books

So now I understand how to this problem..but I dont know why order matters in this question.

So it would be: (6!)/(4!)


But why does order matter in this case?

Also, are there any key words in these types of problems to see if order matters or if order does not matter?


Cheers!

 

[wired202808]

Jill has six different books. She will select one book on Monday and a different one to read on Wednesday. In how many ways can Jill select two different books

So now I understand how to this problem..but I dont know why order matters in this question.

So it would be: (6!)/(4!)


But why does order matter in this case?

Also, are there any key words in these types of problems to see if order matters or if order does not matter?


Cheers!

i did the same problem today the answer 6*5 because order matters.. why because read the question lol "She will select one book on Monday and a different one to read on Wednesday." meaning she CANNOT reuse Monday's book, so the answer is 6*5 = 30.

If order matters then it would have been (6 * 5) / 2

Order doesnt matter if the problem said she put Monday's book back and was able to use it again, otherwise you assume that order matters.

 

[LetsGo2DSchool]

Order matters because you are reading different books on two days. You can look at it this way...

There are 6 books:

A, B, C, D, E, F

Reading book A on Mon. and B on Wed. is not the same as reading book B on Mon. and A on Wed. Thus you have to count both scenarios and order matters.