contestada

The student council at Richmond High School
is made up of 646 female students 229
seniors, and 6% female seniors.
If a student is selected at random, what is the
probability, as a decimal to the nearest
hundredth, that the student is female given that
the student is a senior?

Respuesta :

Answer:

[tex]P(F/S)=0.216[/tex]

Step-by-step explanation:

Let's call F the event that the student is female and S the event that the student is senior.

So, we need to find the probability P(F/S) that a student is female given that  the student is a senior. P(F/S) is calculated as:

P(F/S) = P(F∩S)/P(S)

Then, the probability P(F∩S) that a student is female and senior is equal to 0.06

On the other hand, we can calculate the total number of students x using the following equation as:

[tex]\frac{646}{x}+\frac{229}{x}-0.06=1[/tex]

Where 646/x is the percentage of female students, 229/x is the percentage of senior students and 0.06 is the percentage of female seniors.

Then, solving for x we get that the number of students is 825.4719

Additionally, the probability P(S) that a student is a senior is equal to:

[tex]P=\frac{229}{825.47} =0.2774[/tex]

Because there are 825.47 students and 229 are senior.

So, P(F/S) is equal to:

[tex]P(F/S)=\frac{0.06}{0.2774}=0.216[/tex]