Respuesta :
Answer:
0.0245 and 0.2696
Step-by-step explanation:
Given that there are six teachers, five parents of students, and seven alumni.
A committee of three people is selected at random from the above set
Without any condition, we see that total number of selecting three persons from these 18 persons is [tex]18C3 =\frac{18(17)(16)}{3!} =816[/tex]
a) the committee consists of all teachers
No of ways of selecting all teachers from 6 teachers = [tex]6C3 = 20[/tex]
Probability of the event that the committee consists of all teachers
=[tex]\frac{20}{816} =0.0245[/tex]
b) the committee has no teachers
This is equivalent to selecting 3 persons from 12 non teachers
= [tex]12C3=220[/tex] ways
the probability of the event that the committee has no teachers=[tex]\frac{220}{816} =0.2696[/tex]
