We are told that at the conference, there is a total of 12 math, 9 science, 3 music and 6 social studies teachers.
Recall that the experimental probability of an event measures the likelihood that the event occurs based on the actual results of an experiment.
P(Event)= Number of times the event occurs/Number of times the experiment is done
We want to find the probability of selecting a teacher that is not a music teacher. Note that this is the complement of selecting a music teacher. The sum of the probability of an event and the probability of its complement is 1.
P(Event)+P(Not event)=1
Let's start by finding the probability of selecting a music teacher, which will be our event. The number of times the event occurs is the number of music teachers, 3, and the number of times the experiment is done is the total number of teachers, 30.
P( Music)= Number of musicteachers/Number of teacheres= 3/30
The experimental probability of selecting a music teacher is 330. Let's now find the probability of its complement, which is selecting a teacher that is not a music teacher.
