Question 167113
how many ways can six different books be arranged on a shelf if one of the books is a dictionary  and it must be listed first or last?
------------
# of ways to place the dictionary: 2
# of ways to arrange the other 5 books: 5!
---------------
Total # of arrangements: 2*5! = 2*120 = 240 ways
=====================
Cheers,
Stan H.