Choose 3 then 2 then 1; 3*2*1 = 6 ways.
Ill skip the factorials and just give you what the calculator does in the end. 8*7*6*5*4*3= 20,160
12!/(5!*7!)The number of ways to arrange nitems is n!, where "!" is the factorial function. The number of ways we can arrange the 12 books is therefore 12!. However, we don't really care what order the first 5 books are in, or what order the last 7 books are in, as long as they're the same books. We therefore divide by the number of ways to arrange 5 books and the number of ways to arrange 7 books.
2. If the books are x and y, then xy or yx are the only possible ways. Unless you allow for one book to the side of the other, one bok on top of the other, one book leaning partially on the other, etc. In that case, there are an infinite number of ways.
6 ways
If the librarian follows a standard scheme, such as the Dewey Decimal, then there is essentially only one way. If the librarian arranged books randomly it would become extremely difficult to find any books: the library would become unusable and the librarian would get sacked. So again not many ways of arranging books before you stop being a librarian.
30 ways.
The answer to this one is 24. You can do this mathematically by 4*3*2*1.
120. You do 5*4*3*2*1=120. you multiply the number that you are given for example how many times can books 3 be arranged on a shelf you multiply 3*2*1=6 that is your answer
5 books can be lined up on a shelf in (5 x 4 x 3 x 2 x 1) = 120 different sequences.
Yes. They are real.
The answer would be 7! or (7*6*5*4*3*2*1)=5040
Choose 3 then 2 then 1; 3*2*1 = 6 ways.
There are only 5 places on the shelf. You have 7 books to choose from. We will ignore the order of the books on the shelf. The first place can be filled from a choice of 7 books, the next place from 6, the next place from 5, the next from 4, and the last of the 5 places from 3 books. So the number of ways of choosing the 5 is found from 7 * 6 * 5 * 4 * 3 = 2520
Ill skip the factorials and just give you what the calculator does in the end. 8*7*6*5*4*3= 20,160
Answerthe answer is 24 WHICH is the result of the multiplication: 4x 3 x 2 x 1 = 24. You can try it practically as: Numbering books as A,B, C, and D then the variations are:ABCDABDCBACDBADCCDABCDBADCABDCBABCADBCDACBADCBDAADBCADCBDABCDACBBDACBDCADBACDBCAACBDACDBCABDCADB
There are seven books on the floor. Let x be the number of books on the floor. The number of books on the shelf is 2 + 3x. From the information given, 3x + 2 = number of books on the shelf. Substitute x=7 into 3x + 2 to find the answer. So, there are 23 books on the shelf.