Giving a test to a group of students, the grades and gender are summarized below
A B C Total
Male 4 17 20 41
Female 15 7 19 41
Total 19 24 39 82
If one student is chosen at random,
Find the probability that the student did NOT get an "B"
Hey look, I just did the not a female with A. Now you do this one.
To find the probability that a student did NOT get a "B", we need to determine the total number of students who did not get a "B" and divide it by the total number of students.
Let's start by calculating the total number of students who did not get a "B". We can obtain this by summing the number of students who got grades other than "B" in each gender category.
For males, we sum the number of students who got grades of "A" and "C":
Total males who did not get a "B" = Number of males with grade "A" + Number of males with grade "C" = 4 + 20 = 24
For females, we sum the number of students who got grades of "A" and "C":
Total females who did not get a "B" = Number of females with grade "A" + Number of females with grade "C" = 15 + 19 = 34
Now, we can calculate the total number of students who did not get a "B" by summing the number of males and females who did not get a "B":
Total students who did not get a "B" = Total males who did not get a "B" + Total females who did not get a "B" = 24 + 34 = 58
Finally, we can calculate the probability by dividing the total number of students who did not get a "B" by the total number of students:
Probability of not getting a "B" = Total students who did not get a "B" / Total number of students = 58 / 82 ≈ 0.7073 (rounded to four decimal places)
Therefore, the probability that a student chosen at random did NOT get a "B" is approximately 0.7073 or 70.73%.