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Bunuel
­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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 ­
­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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The sum of the probability of all possible events = 1
=> P(only one of the two treats) + P(both of the treats) + P(neither of the treats) = 1;
So, certainly, we can't calculate other probabilities if one is given, and if we get to know the P(only one of the two treats) and P(both of the treats), then we can find out P(neither of the treats) which will eventually come out to be 1/2.

So, no single statement is sufficient, and together, they are sufficient to answer the question.
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IMO - C

P(neither) = P(not A and not B)

P(only one)+P(Both)+P(Neither) = 1

St 1 - We don't know anything about probability of both the treats to apply the total probability formula. - Insufficient

St2- We don't know anything about probability of individual treats to apply the total probability formula. - Insufficient

Combined we know

P(only one)+P(Both)+P(Neither) = 1

P(Neither) = 1- {P(only one)+P(Both)}

Hence Sufficient. Option C is correct
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We can easily find the probability of mouse not finding either of the treats by considering the probability of at least finding and subtracting from finding both, hence both statement are sufficient and non is enough.

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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.

Answer: C - Both statements together sufficient to answer the question.

Explanation:
There are 3 outcomes possible:
1. The mouse finds both treats.
2. The mouse finds one of the two treats.
3. The mouse finds neither of the treats.

To find the probability of the 3rd outcome, we need the probability of the other 2, as these two are not dependent on each other, therefore, both statements (1) and (2) together are required to answer the question.

The probability that the mouse will find neither of the treats = 1 - 1/5 - 3/10 = 1/2
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­The answer should be C

We need to find the probability the mouse finds neither treat 
 
The formula can be - P (only A) + P(only B) + P(both) + P(neither) = 1

From A we know that probability of finding exactly one of the two treat, which doesnt tell us anything about the P(both).

From B we know that probability of finding P(both) , which doesnt tell us anything about the P (only A) + P(only B).

Combining both A and B we can get P(neither)
 
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Bunuel
­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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 ­
­1= P(only one) + P(Both) + P(Neither) or P(neither) = P(not finding the first treat). P(not finding the second treat)

Statement 1
P (only one) given is not sufficient as per formula.

Statement 2
P (both) given is not sufficient as per formula.

Statement 1+2 Will give sufficient info to find P(neither)

IMO 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.­

So what are the possible outcomes: 
the moust find 0 treats, 1 treat or 2 treats

And P(0 treat) + P(1 treat) + P(2 treat) = 1

Statement (1): P (1 treat) = 1/5, we don't know P(2 treat), hence INSUFF [Note that we are not give P(atleast 1)]

Statement (2): P (2 treat) = 3/10, we don't know P(1 treat), hence INSUFF

Considering both, we can say P(0 treat) = 1 - 1/5 - 3/10 = 1/2

Hence answer is (C)
 
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Given: In a science experiment, a mouse is placed in a labyrinth with two different treats hidden in it.
Asked: 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.

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

Treat 1Not Treat 1Total
Treat 21/5 -p=.2-p
Not Treat 2px = ?p+x
Total1

With the information provided the value of x can not be ascertained.
NOT SUFFICIENT

(2) The probability that the mouse will find both treats is 3/10.
​​​​​​​
Treat 1Not Treat 1Total
Treat 23/10=.3
Not Treat 2x = ?
Total1
​​​​​​​
With the information provided the value of x can not be ascertained.
NOT SUFFICIENT

(1) + (2) 
(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.

​​​​​​​​​​​​​​
Treat 1Not Treat 1Total
Treat 23/10=.31/5 -p=.2-p.5-p
Not Treat 2px = ?p+x
Total1

(.5-p) + (p+x) = 1
.5 + x = 1
x = 1 - .5 = .5
The probability that the mouse will find neither of the treats = .5
SUFFICIENT

IMO 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. Not suffi
(2) The probability that the mouse will find both treats is 3/10.

Sum of all Probabilities=1
P(both treats)+P(since treat)+P(no treat)=1
Statement (1) and Statement (2) alone are insufficient

1/5+3/10+P(no treat)=1

Hence (1) & (2) together are sufficient. Ans is C
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­Answer C
Explanation
I.Insufficient
II.Insufficient
I+II: We know that the probability of finding neither is 1- P(finding both)-P(finding only one) = 1-3/10-2/10= 5/10
-> Sufficient
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Bunuel
­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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­
 ­
­To determine the probability that the mouse will find neither of the treats, let's analyze the given statements and use them to solve the problem.

### Given Statements

**Statement (1):** The probability that the mouse will find only one of the two treats is \( \frac{1}{5} \).
\[ P(\text{only one}) = \frac{1}{5} \]

**Statement (2):** The probability that the mouse will find both treats is \( \frac{3}{10} \).
\[ P(\text{both}) = \frac{3}{10} \]

### Total Probability

We know that the total probability must sum to 1:
\[ P(\text{neither}) + P(\text{only one}) + P(\text{both}) = 1 \]

We are given:
\[ P(\text{only one}) = \frac{1}{5} \]
\[ P(\text{both}) = \frac{3}{10} \]

Plugging in these values:
\[ P(\text{neither}) + \frac{1}{5} + \frac{3}{10} = 1 \]

To simplify the calculations, convert \(\frac{1}{5}\) to a common denominator with \(\frac{3}{10}\):
\[ \frac{1}{5} = \frac{2}{10} \]

Now, the equation becomes:
\[ P(\text{neither}) + \frac{2}{10} + \frac{3}{10} = 1 \]
\[ P(\text{neither}) + \frac{5}{10} = 1 \]
\[ P(\text{neither}) + \frac{1}{2} = 1 \]
\[ P(\text{neither}) = 1 - \frac{1}{2} \]
\[ P(\text{neither}) = \frac{1}{2} \]

Therefore, using both statements together, we can determine that the probability the mouse will find neither of the treats is \(\frac{1}{2}\).

### Analyzing Sufficiency

- **Statement (1) alone** is insufficient because knowing only \( P(\text{only one}) = \frac{1}{5} \) does not allow us to calculate \( P(\text{neither}) \) without knowing \( P(\text{both}) \).
- **Statement (2) alone** is insufficient because knowing only \( P(\text{both}) = \frac{3}{10} \) does not allow us to calculate \( P(\text{neither}) \) without knowing \( P(\text{only one}) \).

However, **both statements together** provide sufficient information to determine \( P(\text{neither}) \).
Correct Answer: C
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To determine the probability that the mouse will find neither of the treats, we need to understand the probabilities involved in the different possible outcomes:

Finding neither treat
Finding only one treat
Finding both treats

Let's denote:

P(A∪B) as the probability that the mouse finds at least one of the treats.
P(neither) as the probability that the mouse finds neither treat.
We know that:
P(neither)=1−P(A∪B)

Let's analyze each statement to see if they provide sufficient information to find P(neither).

Statement (1):
The probability that the mouse will find only one of the two treats is 1/5

Let's denote:
P(only one)= 1/5

Statement (2):
The probability that the mouse will find both treats is 3/10

Let's denote:
P(both)= 3/10

Combined Analysis:
From both statements, we have:
P(only one)= 1/5
P(both)= 3/10

To find
P(A∪B), we need to sum up the probabilities of finding one or both of the treats:
P(A∪B)=P(only one)+P(both)
P(A∪B)= 1/5 + 3/10

To add these fractions, we need a common denominator:
1/5 = 2/10
P(A∪B)= 2/10 + 3/10 = 5/10 = 1/2

Now, we can find the probability that the mouse will find neither treat: P(neither)=1−P(A∪B)= 1− 1/2 = 1/2

Conclusion:
Both statements together allow us to determine the probability that the mouse will find neither of the treats.

Thus, the correct answer is: C.
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The probability that the mouse will find neither treats is equal to 1- P(mouse will both treats) - P(mouse will find exactly 1 treat)

Statement 1: Probability that mouse will find one of the treats is given. We need to know the probability of mouse finding both the treats too. Insufficient.

Statement 2: Probability of finding both treats is given. Insufficient.

Combining both the statements, we have all we need to answer the probability.

Therefore, C­
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Bunuel
­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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­
 ­
The total probability for all possible outcomes must be 1 = P (finding neither treat) + P(finding exactly one treat) + P(finding both treats)

(1) The probability that the mouse will find only one of the two treats is 1/5. => but we don't know P(both) we cannot find P(neither) => insuff 
(2) The probability that the mouse will find both treats is 3/10. => but we don't know P(only one) we cannot find P(neither) => insuff 
But both statements are suff since we know P(both) and P(only one) and subtract from 1 to get P(neither) => C
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­(1) The probability that the mouse will find only one of the two treats is 1/5.
This does not give The probability that the mouse will find both treats which is essential. 
(2) The probability that the mouse will find both treats is 3/10.
This does not give the The probability that the mouse will find only one of the two treats which is essential. 
Combined, we get the probability that the mouse will find neither of the treats = 1 - (The probability that the mouse will find both treats) - (The probability that the mouse will find only one of the two treats) = 1/2
C - combined sufficient. 
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After resting at the weekend.
We're back to business.
I feel the luck is going to shift to our Green team as we get closer to the end of the Champions.
Let's get started with our explanation for this topic:

Glance - the Question:
Question: We have here kind of Overlap double matrix question with probability.

Rephrase - Reading and Understanding the question:
Given:
                           Find T1           Find T1            Total
-------------------------------------------------------------------------
Find T2         |                      |                    |
-------------------------------------------------------------------------
No Find T2    |                      |        [?]        | 
-------------------------------------------------------------------------
Total             |                      |                    |       100%


Solve: (1)
                           Find T1           Find T1            Total
-------------------------------------------------------------------------
Find T2         |                      |         X          |
-------------------------------------------------------------------------
No Find T2    |          Y           |        [?]        | 
-------------------------------------------------------------------------
Total             |                      |                    |       100%

X+Y = 20%
Insufficient. We can eliminate by trying to cases. you can see clearly that there could me many possible solutions.

(2)
                           Find T1           Find T1            Total
-------------------------------------------------------------------------
Find T2         |        30%       |                     |
-------------------------------------------------------------------------
No Find T2    |                      |        [?]        | 
-------------------------------------------------------------------------
Total             |                      |                    |       100%

Insufficient. We can eliminate by trying to cases. you can see clearly that there could me many possible solutions.


(1)+(2)
                           Find T1      |    Find T1      |        Total
---------------------------------------------------------------------------
Find T2         |        30%        |         X          |      30% + X
---------------------------------------------------------------------------
No Find T2    |          Y           |        [?]        |      70% - X
---------------------------------------------------------------------------
Total             |      30 + Y       |       70 - Y     |        100%

[?] = 70 - Y - X    =>    70 - (Y + X)     =>  
X + Y = 20%       =>   70% - 20% = 50%
Sufficient :)
Answer Choice C


THE END
I hope you liked the explanation, I have tried my best here.
Let me know if you have any questions about this question or my explanation.
­  
 
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