Since the order matters we use Permutation in a calculator it looks like nPr: the n flags arranged into r places.
in this case: 10 flags arranged into 4 places.
the top position would have 10 choices of flags
second position, 9 choices
third position, 8 choices
last position only seven choices.
10 * 9 * 8 * 7 = 5040 or
nPr = 10P4= 5040
Find the number of ways that 4 flags can be displayed on a flagpole, one above the other, if 10 different flags are available.
1 answer