Question

a researcher selected a group of 6 teachers to determine how many times each teacher had students after school. the researcher recorded the findings in the table below.

teacher	number of occasions
2	15
3	12
4	20
5	15
6	20
total	100

what is the empirical probability that teacher 4 will have students after school?
80%
15%
20%
25%

Explanation:

Step1: Recall experimental - probability formula

Experimental probability $P(E)=\frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}}$

Step2: Identify values from table

The total number of teachers surveyed is $6$ (number of rows in the table). The number of teachers who have students after - school is the sum of the non - zero values in the "Number of Students" column. $18 + 15+12 + 20+15 + 18=98$. But we are interested in the number of teachers, not students. The number of teachers who have students after - school is $6$ (since all $6$ teachers have some non - zero number of students). The total number of teachers surveyed is $6$.
So the experimental probability $P=\frac{6}{6} = 1 = 100\%$

Answer:

$100\%$