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There is a total of 120 marbles in a box, each of which is r
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27 Aug 2020, 09:55
27 Aug 2020, 09:55
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There is a total of 120 marbles in a box, each of which is red, green, blue, or white. If one marble is drawn from the box at random, the probability that it will be white is 1/4 and the probability that it will be green is 1/3. What is the probability that the marble will be either red or blue ?
(A) 1/6
(B) 1/4
(C) 2/7
(D) 1/3
(E) 5/12
(A) 1/6
(B) 1/4
(C) 2/7
(D) 1/3
(E) 5/12
Re: There is a total of 120 marbles in a box, each of which is r
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27 Aug 2020, 09:55
27 Aug 2020, 09:55
Expert Reply
Post A Detailed Correct Solution For The Above Questions And Get A Kudos.
Question From Our New Project: GRE Quant Challenge Questions Daily - NEW EDITION!
For more theory and practice see our GRE - Math Book
Question From Our New Project: GRE Quant Challenge Questions Daily - NEW EDITION!
For more theory and practice see our GRE - Math Book
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Re: There is a total of 120 marbles in a box, each of which is r
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27 Aug 2020, 10:32
27 Aug 2020, 10:32
Carcass wrote:
There is a total of 120 marbles in a box, each of which is red, green, blue, or white. If one marble is drawn from the box at random, the probability that it will be white is 1/4 and the probability that it will be green is 1/3. What is the probability that the marble will be either red or blue ?
(A) 1/6
(B) 1/4
(C) 2/7
(D) 1/3
(E) 5/12
(A) 1/6
(B) 1/4
(C) 2/7
(D) 1/3
(E) 5/12
...the probability that it [the marble] will be white is 1/4
So, 1/4 of the 120 marbles are white.
In other words, there are 30 white marbles.
...the probability that it [the marble] will be green is 1/3
So, 1/3 of the 120 marbles are green .
In other words, there are 40 green marbles.
Altogether, there are 70 marbles that are EITHER white or green.
This means that the remaining 50 marbles are EITHER red or blue.
So, P(selected marble is EITHER red or blue) = 50/120
= 5/12
Answer: E
Cheers,
Brent
