Question

Of all the Sunny Club members in a particular city, 25% prefer swimming on weekends and 75% prefer swimming on weekdays. 10% of the members in the city prefer swimming on weekends and are female. 55% of the members in the city prefer swimming on weekdays and are female. What is the probability that a randomly selected club member is female, given that the person prefers swimming on weekends?

Answer 1

(A).19, (B).20, (C).24, (D).40, (E).55

Answer 2

just to be clear.. in the question its mentioned 10 percent of the members in the CITY!?

from where did this CITY come from? oO

Answer 3

Im not sure...

Answer 4

i think its basically talking about the club itself.. anyhow.. you do know.. what is asked here is reverse probability and needs Baye's theorem to solve it

Answer 5

Tried to find Baye's Theorem on Google wasn't quite sure what i was looking at.

Answer 6

lol.. you haven't done Bayes theorem in class? maybe you have and you don't know its called so .. ??

anyhow .. can you start the problem?! ll help you!

Answer 7

ok, so 10% of the 25% of people that prefer to swim on weekends are female. I multiplyed 10% and 25% getting .025

Answer 8

And then 55% of the 75% are females who prefer to swim on the weekdays. I also multiply those together getting .4125

Answer 9

So to get the answer am i suppose to divide.025 by something?

Answer 10

Divide .25 by .10= .40 is what i think the answer is?

Answer 11

given that person prefers to swim on wekeend, it says that 10% are female.

So P(Female | weekend) = 0.1

Answer 12

Yea, i thought i already knew that.

Answer 13

@Mashy you still here?

Answer 14

\[0.25x=0.1\]
\[x=\frac{0.1}{0.25}=you\ can\ calculate\]

Answer 15

@Mr.Man420 The probability tree above confirms that 0.4 is correct :)

Answer 16

Thank you @kropot72 thats what i thought.

Answer 17

You're welcome :)