SOLUTION: Paige Turner loves finite mathematics. She has 4 books about probability and 3 books about matrices. How many ways can she place these books on the same shelf in a row if:

Algebra ->  Permutations -> SOLUTION: Paige Turner loves finite mathematics. She has 4 books about probability and 3 books about matrices. How many ways can she place these books on the same shelf in a row if:       Log On


   



Question 1122247: Paige Turner loves finite mathematics. She has 4 books about probability and 3 books about matrices.
How many ways can she place these books on the same shelf in a row if:
a) there are no restrictions.


b) the books about probability are next to each other but the others could be anywhere on the shelf.


c) books are organized by their topic (probability books are next to each other and matrix books are next to each other).

Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
Paige Turner — love it!
a) 7! = highlight%28+5040+%29+
b) Treat the 4 probability books like a unit, that gives 4!=24 ways of arranging. However, for each one of these arrangements, the 4 probability books can be arranged in 4! ways, therefore 4! * 4! = 24 * 24 = +highlight%28576%29+
c) 4!*3!*2 = 24*6*2 = highlight%28+288%29+ (*2 because each subject can be on left or right)