+0  
 
0
2
1
avatar+209 

I have $3$ different mathematics textbooks, $2$ different psychology textbooks, and $2$ different chemistry textbooks. In how many ways can I place the $7$ textbooks on a bookshelf, in a row?

 Mar 31, 2024
 #1
avatar+818 
0

 

I have $3$ different mathematics textbooks, $2$ different psychology textbooks, and $2$ different chemistry textbooks. In how many ways can I place the $7$ textbooks on a bookshelf, in a row?  

 

                 7!             5040  

7P7  =  –––––––  =  ––––––  =  5040       

             (7 – 7)!           1   

 

You might be alarmed by seeing zero in the denominator,   

which is the most verboten condition known in math,   

but zero factorial is defined as 1 so it's okay.  

.

 Apr 10, 2024

3 Online Users

avatar
avatar