15 students in 6A are divided into 3 groups for a party , 3 students are organizers , 4 students are planners and 8 students are responsible for the food
Mandy , Helen and Sue are 6A students are responsible for the party
find the probability that thy are in the same group
thanks
+33657 This is (nbr of ways of arranging 3 people in a group of 3 + nbr of ways of arranging 3 people in a group of 4 + nbr of ways of arranging 3 people in a group of 8)/(nbr of ways of arranging 3 people in a group of 15):
((3!(3−3)!)+(4!(4−3)!)+(8!(8−3)!))(15!(15−3)!)=61455=0.1340659340659341
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