SOLUTION: Giving a test to a group of students, the grades and gender are summarized below A B C Total Male 16 22 32 70 Female 13 17 25 55 Total 29 39 57 125 Determine the following

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Question 1210443: Giving a test to a group of students, the grades and gender are summarized below
A B C Total
Male 16 22 32 70
Female 13 17 25 55
Total 29 39 57 125
Determine the following probabilities. Write your answers as reduced fractions.
We randomly select a student. What is the probability that this student got a B?
P =
We randomly select a student. What is the probability that this student is a male who got a B?
P =
We randomly select a male student. What is the probability that he got a B?
P
We randomly select a student who got a B. What is the probability that this student is a male?
P =
Found 3 solutions by Edwin McCravy, ikleyn, math_tutor2020:
Answer by Edwin McCravy(20081)   (Show Source):
You can put this solution on YOUR website!

Giving a test to a group of students, the grades and gender are summarized below: A B C Total Male 16 22 32 70 Female 13 17 25 55 Total 29 39 57 125 Determine the following probabilities. Write your answers as reduced fractions. ----------------------------------------- We randomly select a student. What is the probability that this student got a B? P(B) = 39/125 ----------------------------------------- We randomly select a student. What is the probability that this student is a male who got a B? P(M AND B) = 22/125 ----------------------------------------- We randomly select a male student. What is the probability that he got a B? P(B|M) = P(B AND M)/P(M) = ----------------------------------------- We randomly select a student who got a B. What is the probability that this student is a male? P(B|M) = P(M AND B)/P(B) = Edwin

Answer by ikleyn(53763)   (Show Source):
You can put this solution on YOUR website!
.

In the post by Edwin, his answer to the last question, 39/70, is incorrect.

The correct answer is 22/39.

Answer by math_tutor2020(3835)   (Show Source):
You can put this solution on YOUR website!

A B C Total
Male 16 22 32 70
Female 13 17 25 55
Total 29 39 57 125

We randomly select a student. What is the probability that this student got a B?
P = (number who got a B)/(number total)
P = 39/125

We randomly select a student. What is the probability that this student is a male who got a B?
P = (number of men who got a B)/(number total)
P = 22/125

We randomly select a male student. What is the probability that he got a B?
P = (number of men who got a B)/(number of men)
P = 22/70
P = 11/35

We randomly select a student who got a B. What is the probability that this student is a male?
P = (number of men who got a B)/(number who got a B)
P = 22/39