How many students who studied for the quiz passed? What is the total number of students who studied?
About 0.364
Practice makes perfect
We have a two-way frequency table that shows information about the students who took a quiz. Since we want to know the relative frequency of selecting a student who did not study for the quiz and failed, let's highlight the number of students who did not study for the quiz and failed and the total of students who did not study.
Studied
Did not study
Totals
Passed
19
7
26
Failed
1
4
5
Totals
20
11
31
Let's now find the relative frequency of selecting a student who did not study for the quiz and failed when choosing a student at random.
P(Did not study and failed) = Did not study and failed/Did not study [1em]
P(Did not study and failed) = 4/11≈ 0.364
