Provide a real-world example 0f how permutations and combinations can be used. Explain the details of your example.

Permutation is the number of ways you can arrange things.
The order of arranging is also considered in
permutations.

The combination is the different number of
ways we choose. In combination the order is not
considered.

Permutation or diffrent ways of  arranging 2
marbles red green in 3 places shelves A,B and C.

A    B   
C

r     g    -

g    r    
-

r     -    g

g    -    
r

-    g     r

-    r    
g

The  number of arrangements above  is  3P2 = 3!/(3-2)!
=3!/1! = 3*2 *1 = 6.

In combinations it is the number of
diffrent things you select.

The number of two marbles 
group you can  do in this case  of  3  diffrent marbles green, blue and red  is 3 as the
the number of groups you can form are :

 gr,gb,
br.

Here gr and rb are not different, gb and bg are not
different and similarly br and rb are not different.( Whereas , in permutation, gr  and
rg  , gb and bg, and br and rb are treated different).