From a committee of 8 persons, a chairman and a vice chairman are to be chosen in such a way that one person cannot hold more than one position.
Here, the number of ways of choosing a chairman and a vice chairman is the permutation of 8 different objects taken 2 at a time.
Thus, required number of ways =\(^8P_2=\frac{8!}{(8-2)!}=\frac{8!}{6!}\)
\(=\frac{8\times7\times6!}{6!}=8\times7=56\)
Find the mean deviation about the mean for the data 38, 70, 48, 40, 42, 55, 63, 46, 54, 44.
Permutation is the method or the act of arranging members of a set into an order or a sequence.
Combination is the method of forming subsets by selecting data from a larger set in a way that the selection order does not matter.