in a room filled with 6 people , all 6 people have exactly 2 siblings in the room . if two individuals are selected from the room at random , what is the probability that those two individuals are not siblings ?
"the 6 people consist of two sets of 3 siblings . the number of ways to choose 2 people is 6 c 2 = 15 . the number of ways to choose 2 from the first group of siblings is 3 c 2 = 3 . the number of ways to choose 2 from the second group of siblings is 3 c 2 = 3 . the number of ways to choose 2 people who are siblings is 3 + 3 = 6 . the number of ways to choose 2 people who are not siblings is 15 - 6 = 9 . p ( the two people are not siblings ) = 9 / 15 = 3 / 5 the answer is a ."
divide(multiply(6, subtract(subtract(6, 2), 2)), multiply(6, subtract(6, 2)))