SOLUTION: Suppose a math class contains 34 students, 21 females (three of whom speak French) and 13 males (two of whom speak French). Compute the probability that a randomly selected student

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Question 1150193: Suppose a math class contains 34 students, 21 females (three of whom speak French) and 13 males (two of whom speak French). Compute the probability that a randomly selected student speaks French, given that the student is female.
Found 2 solutions by Boreal, ikleyn:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
F+ F- Total
M 2 11 13
F 3 18 21
5 29 34
given speaks F (5) probability female is 60%, 3/5

Answer by ikleyn(52779) About Me  (Show Source):
You can put this solution on YOUR website!
.
Suppose a math class contains 34 students, 21 females (three of whom speak French) and 13 males (two of whom speak French).
Compute the probability that a randomly selected student speaks French, given that the student is female.
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The answer is  MORE THAN OBVIOUS.


This probability is  3%2F21 = 1%2F7.    <<<===---   A N S W E R


It is because 3 of the 21 females speak French (given).


This part of the condition " . . . given that the student is female"  means that actually we select the random person among women.


By using this interpretation, we get the solution  EXTREMELY simple.

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Notice. Tutor @Boreal misread the problem and got incorrect answer.