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­In a science experiment, a mouse is placed in a labyrinth with two different treats hidden in it. What is the probability that the mouse will find neither of the treats?

P(Only 1) + P(both) + P(neither) = 1

(1) The probability that the mouse will find only one of the two treats is 1/5.
P(Only 1)= 1/5
We still dont know P(both)
I is insufficient.

(2) The probability that the mouse will find both treats is 3/10.
P(both) = 3/10
We still dont know P(Only 1)
II is insufficient.

Combining  1 & 2:
P(Only 1)= 1/5
P(both) = 3/10
The only unknown is P(neither) which we can calculate using
P(Only 1) + P(both) + P(neither) = 1

Ans C
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­In a science experiment, a mouse is placed in a labyrinth with two different treats hidden in it. What is the probability that the mouse will find neither of the treats?

(1) The probability that the mouse will find only one of the two treats is 1/5.
(2) The probability that the mouse will find both treats is 3/10.

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked.
C. BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.
D. EACH statement ALONE is sufficient to answer the question asked.
E. Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.

 


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­In a science experiment, a mouse is placed in a labyrinth with two different treats hidden in it. What is the probability that the mouse will find neither of the treats?

(1) The probability that the mouse will find only one of the two treats is 1/5.
(2) The probability that the mouse will find both treats is 3/10.

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked.
C. BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.
D. EACH statement ALONE is sufficient to answer the question asked. => CORRECT
E. Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.


(1) One of the treat: 1/5 => Two of the treat:2/5 => None of the treats: 3/5
(2) Both treats: 3/10 => None of the treats => 7/10
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KarishmaB here are the probabilities of finding each treat the same ? How do we know whether they are same or not?

And if it were the same , then in that case would A be sufficient since we could find prob of both as 1/10*1/10 and hence find prob of neither?
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Elite097
KarishmaB here are the probabilities of finding each treat the same ? How do we know whether they are same or not?

And if it were the same , then in that case would A be sufficient since we could find prob of both as 1/10*1/10 and hence find prob of neither?
­
We are not given that the probability of finding either treat is the same. If we are not given, we must assume that they could be different. They could turn out to be same too but we cannot assume it. 
Even if they were given to be same, we do not know the relation between the two events. We cannot assume they must be independent so we cannot multiply their individual probabilities. Besides, we are given the probability that only one treat is found. It does not include their combined probability. 
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KarishmaB

Elite097
KarishmaB here are the probabilities of finding each treat the same ? How do we know whether they are same or not?

And if it were the same , then in that case would A be sufficient since we could find prob of both as 1/10*1/10 and hence find prob of neither?
­
We are not given that the probability of finding either treat is the same. If we are not given, we must assume that they could be different. They could turn out to be same too but we cannot assume it. 
Even if they were given to be same, we do not know the relation between the two events. We cannot assume they must be independent so we cannot multiply their individual probabilities. Besides, we are given the probability that only one treat is found. It does not include their combined probability. 
1. ­KarishmaB makes sense but it seems you have missed a point. In this case, FINDING one treat is independent from FINDING another treat because the two events have no relation with each other, so if we knew that their probabilities are the same, then wouldnt we multiply them to find the combined probabilities which would make A sufficient?
2. Also im not sure why you think they arent independent?­
3. If we knew they are idnep and they have the same probability, then why would we still need to know prob of both? Wouldnt we be able to calculate by multiplhying 1/10*1/10? Is there something I am missing here?
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In this case it doesnt matter because we arent finding out the "both" section by using any independence formula but the standard P(all)=1 meaning its exhaustive.
Archit3110


­P of neither = 1- ( P(a)+ P(b)- P ( a and b) )
#1
The probability that the mouse will find only one of the two treats is 1/5.
no info about other event and together insufficient
#2
The probability that the mouse will find both treats is 3/10
no info about other event insufficient
from 1 &2
P ( a ) or P ( b ) is 1/5 and its not clear whether its an independent or dependent event
insufficient together
OPTION E is correct

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