Question

In a class of students, the following data table summarizes how many students passed a test and completed the homework due the day of the test. What is the probability that a student passed the test given that they completed the homework?
Passed the test Failed the test
Completed the homework 14 3
Did not complete the homework 4 6

Answer 1

We want P(passed | completed homework) = (number who passed and completed) / (number who completed) = 14 / (14+3) = 14/17 ≈ 0.8235 (about 82.35%).