A-committee-of-five-is-to-be-chosen-from-a-group-of-9-people-The-probability-that-a-certain-married-couple-will-either-serve-together-or-not-at-all-is-

Question Number 93330 by Shakhzod last updated on 12/May/20

A committee of five is to be chosen from

a group of 9 people . The probability

that a certain married couple will either

serve together or not at all is

Answered by prakash jain last updated on 12/May/20

let members be p_{1,} p_{2}, \dots, p_{9}

Let (p_{1}, p_{2}) be the married couple

Comittee with married couple

as members =^{7} C_{3} = 35

Comittee with both are not

memers =^{7} C_{5} = 21

Total options for comitees =^{9} C_{5} = 126

required probability = \frac{35 + 21}{126} = \frac{4}{11}