. What is the probability of selecting a group of 3 people to set the table in 2.?

Question

VI. You and 20 of your friends have decided to form an internet corporation with three (3) key positions. You have decided to select a President (PR), a Vice-President (VP) and a chief financial officer (CFO).

Answer 1

Talita

It's possible to choose from 21 people as it is you and 20 of your friends.

PR can be chosen in 21 ways.

VP can then be chosen in 20 ways (as one person has become PR)

CFO then can be chosen in 19 ways

So you can choose the combination in 21 x 20 x 19 = 7980 ways. This is the same as 21 P 3

Mike

Answer 2

(20 pick 3) = 20*19*18 = 6840 ways