The partially completed probability tree diagram shows the chances of

Question

The partially completed probability tree diagram shows the chances of an outdoor concert taking place or being canceled when rain might or might not occur. What is the probability that the concert takes place given that it rains?

(A) 2%
(B) 15%
(C) 25%
(D) 38%
(E) 85%

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Attachment:

2018-03-23_1101.png

DavidTutorexamPAL · Answer

Since the calculation we're asked to do is straightforward, we'll just do it.
This is a Precise approach.

Since we know that it rains, we can ignore the bottom part of the diagram.
Looking inside the 'rain' part of the diagram, 75% of cancellation means 25% of no cancellation

(C) is our answer.

sameeruce08 · Answer

i will go with 15%

probability of rain * concert will take place
=.6*.25
=15%

Shobhit7 · Answer

P(rain) x P(concert)=
0.6 x 0.25= 0.15

Hence, 15%
Ans B

Posted from my mobile device

MT1988 · Answer

The word given is problematic. If the wordings May hve added a uncertainty that it May rain then answer would have been 15%
Have selected 15 but not sure could be 25 also

chacinluis · Answer

Again. One of those really misleading questions. The word "given" implies we have a conditional probability.
Therefore we are looking for P(C|R).

Event R= it rains
Event C= concert takes place

So P(C|R)=0.25
Answer: C

But it seems according to the answer explanation from where the question came from that they want us to find P(C,R). That is, the probability that the concert takes place AND it rains.
Therefore from

P(C|R)=P(C,R)/P(R)
we get
P(C,R)=P(C|R)*P(R)=0.25*0.6=0.15
Answer: B

nik29672 · Answer

Hey! Can someone please tell me how can we confirm if we have answered correctly? 
and what's the right answer to this question - B or C ?

Bunuel · Answer

See "Spoiler: OA" in the original post? Click on it to reveal the OA (official answer).

nkme2007 · Answer

From the Question.. Probability to rain = 0.6
Probability that the concert takes place while raining = 0.25

Total probability = 0.6*0.25 = 0.15 = 15%

OA: B

nik29672 · Answer

Posted from my mobile device

madzaka · Answer

This question is written as bad as it possibly can. If you just solve it for the picture you get the right answer, but if you can read English you get the wrong one just because of it saying GIVEN THAT IT RAINS which makes the problem start from that point on. This is a huge mistake and has no place in GMAT. Shame on whoever created that question

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The partially completed probability tree diagram shows the chances of

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