7654321 = 7! = 5,040
Five numbers can be arranged in 5! = 120 ways.
24 ways.
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
49
81
The number of ways that 15 books can be arranged on a shelf is the same as the number of permutations of 15 things taken 15 at a time. This is 15 factorial, or 15!, and is 1,307,674,368,000.
7654321 = 7! = 5,040
There are 2*5! = 240 ways.
The answer depends on how many books on each subject there are.
The number of permutations of five things taken five at a time is five factorial, or 120.
it depends on the shelf of course
how many ways can 8 letters be arranged
If the books have to be the correct way up and spine outwards: 7! ways =7x6x5x4x3x2x1 =5040 ways. If the books can be any way in (upside down, spine inward, etc.): (7!x4^7) ways =7x4x6x4x5x4x4x4x3x4x2x4x1x4 =82,575,360 ways
Five numbers can be arranged in 5! = 120 ways.
9 x 8 x 7 x 6 x 5
4! = 24, they can be arranged in 24 different ways