the director of health services is concerned about a possible flu outbreak at her college. she surveyed 100…

the director of health services is concerned about a possible flu outbreak at her college. she surveyed 100 randomly selected residents from the colleges dormitories to see whether they had received a preventative flu shot. the results are shown below. what is the probability that a dormitory resident chosen at random from this group has had a flu shot, given that he is male? residents at college dormitories male female total had flu shot 39 41 80 didnt have flu shot 12 8 20 total 51 49 100

the director of health services is concerned about a possible flu outbreak at her college. she surveyed 100 randomly selected residents from the colleges dormitories to see whether they had received a preventative flu shot. the results are shown below. what is the probability that a dormitory resident chosen at random from this group has had a flu shot, given that he is male? residents at college dormitories male female total had flu shot 39 41 80 didnt have flu shot 12 8 20 total 51 49 100

Answer

Explanation:

Step1: Recall conditional - probability formula

The formula for conditional probability is $P(A|B)=\frac{P(A\cap B)}{P(B)}$. In terms of counts, if $A$ is the event of having a flu - shot and $B$ is the event of being male, $P(A|B)=\frac{n(A\cap B)}{n(B)}$, where $n(A\cap B)$ is the number of males who had a flu shot and $n(B)$ is the number of males.

Step2: Identify values from the table

From the table, the number of males who had a flu shot $n(A\cap B) = 39$, and the number of males $n(B)=51$.

Step3: Calculate the probability

$P(A|B)=\frac{39}{51}=\frac{13}{17}$

Answer:

$\frac{13}{17}$