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A bag has 20 marbles that are either black or white.
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25 Dec 2018, 15:14
25 Dec 2018, 15:14
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Question Stats:
81% (01:09) correct
18% (00:45) wrong based on 126 sessions
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A bag has 20 marbles that are either black or white.
Quantity A |
Quantity B |
The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 black marbles are selected |
The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 white marbles are selected |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Re: A bag has 20 marbles that are either black or white.
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26 Dec 2018, 13:12
26 Dec 2018, 13:12
2
Answer: D
20 marbles: black or white
A: The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 black marbles are selected
B: The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 white marbles are selected
Since we don’t have any information about the number of black or white ones, we can't decide which one is more or less, therefore, we can't construe about their probabilities. hence, the answer is D.
20 marbles: black or white
A: The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 black marbles are selected
B: The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 white marbles are selected
Since we don’t have any information about the number of black or white ones, we can't decide which one is more or less, therefore, we can't construe about their probabilities. hence, the answer is D.
Re: A bag has 20 marbles that are either black or white.
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27 Dec 2018, 00:25
27 Dec 2018, 00:25
2
Expert Reply
Carcass wrote:
A bag has 20 marbles that are either black or white.
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Quantity A |
Quantity B |
The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 black marbles are selected |
The number of times one must randomly draw a marble from the bag, without replacing it, to ensure that at least 4 white marbles are selected |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Our answer will be the marbles which are lesser than the other.
Say there are 5 black and 15 whites..
We can be sure that 4 whites are there if we pick 5+4=9 and that 4 blacks are there if we pick 15+4=19..
But we are not aware of the number of black or white marbles.
Thus D
