OG 12th Edition Qn

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OG 12th Edition Qn

by crimson2283 » Tue Mar 01, 2011 5:22 am

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Sixty percent of the members of a study group are women, and 45 percent of those women are lawyers. If one member of the study group is to be selected at random, what is the probability that the member selected is a woman lawyer?

(A) 0.10
(B) 0.15
(C) 0.27
(D) 0.33
(E) 0.45

Out of 60 women if 45% are lawyers, then 27 members are lawyers. Won't probability that the member selected is a woman lawyer be 27/60 - 0.45?

OA - C

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by Anurag@Gurome » Tue Mar 01, 2011 6:30 am
crimson2283 wrote:Sixty percent of the members of a study group are women, and 45 percent of those women are lawyers. If one member of the study group is to be selected at random, what is the probability that the member selected is a woman lawyer?

(A) 0.10
(B) 0.15
(C) 0.27
(D) 0.33
(E) 0.45
Say, the number of members of that study group is 100.
Therefore, number of women in that study group = 60% of 100 = 60
Therefore, number of lawyers out of these 60 women in that study group = 45% of 60 = 27

Hence, required probability = (Number of woman lawyers)/(Total number of people in that study group) = 27/100 = 0.27

The correct answer is C.
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by Jeff@TargetTestPrep » Fri Jun 26, 2015 9:06 am
crimson2283 wrote:Sixty percent of the members of a study group are women, and 45 percent of those women are lawyers. If one member of the study group is to be selected at random, what is the probability that the member selected is a woman lawyer?

(A) 0.10
(B) 0.15
(C) 0.27
(D) 0.33
(E) 0.45

Out of 60 women if 45% are lawyers, then 27 members are lawyers. Won't probability that the member selected is a woman lawyer be 27/60 - 0.45?

OA - C

Solution:

This is a two-part probability question. We should first notice that because our answer choices are in decimal form, we can choose a convenient value to represent the total number of members of the study group. The best number to use is 100.

We are first told that 60 percent of the members in the group are women. Thus, we can say:

0.6 x 100 = 60 women

We are next told that 45 percent of these 60 women are lawyers. We can then say:

0.45 x 60 = 27 women lawyers

Finally, we need to determine the probability of selecting a woman lawyer from the group. Since there are 100 total members, and 27 of them are women lawyers, the probability is 27/100 = 0.27.

Answer:C

Jeffrey Miller
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[email protected]

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by [email protected] » Sun Mar 18, 2018 7:10 pm
Hi All,

We're told 60% of the members of a study group are women, and 45 % of THOSE WOMEN are lawyers. If one member of the study group is to be selected at random, we're asked for the probability that the member selected is a woman lawyer. This question can be solved rather easily by TESTing VALUES. It can also be solved with a bit of Algebra.

If the TOTAL number of people = X, then....
the TOTAL WOMEN = (.6)(X) = .6X, and...
the TOTAL WOMEN LAWYERS = (.45)(.6X) = .27X

Thus, the probability of randomly selecting a woman lawyer from the group is .27

Final Answer: C

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Rich
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