Problema Solution
A tv network has 15 comedy shows that it plans to air. It wants to order 4 of them for a special Monday lineup. How many different possible lineups are there for Monday night?
Answer provided by our tutors
The number of permutations of n objects taken r at a time can be written as
nPr = n!/(n - r)!
in our case we have n = 15 and r = 4
15P4 = 15!/(15 - 4)! = 15!/11! = 12*13*14*15 = 3260 different possible lineups
there are 3260 different possible lineups.