Answer to Question #91873 in Statistics and Probability for Tran

Question

There are four children in Mr. Martin’s class. Three of them will be selected to be hall monitors. How many combinations of hall monitors are possible?

Answer 1

Answer: 4

Explanation

We get all possible triples of children from four children by choosing one child from four ones, which is not included into a triple, so four combinations of hall monitors are possible.

We get the same answer, using the combinatorial analysis formula of the number of possible combinations of 4 objects taken 3 at a time: C(4,3)=4!/3!/(4-3)!=4.