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09 Aug 2022, 01:30
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A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
38% (02:38) correct
62%
(02:49)
wrong
based on 90
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At a certain car dealership, the probability of selecting a car of red color by customer is 1/6. The probability of selecting a car of X model is 5/13. Which of the following could not be the probability of selecting a car, which is either of red color or X model or both?
(A) 3/8
(B) 5/11
(C) 5/13
(D) 7/13
(E) 8/15
Are You Up For the Challenge: 700 Level Questions
(A) 3/8
(B) 5/11
(C) 5/13
(D) 7/13
(E) 8/15
Are You Up For the Challenge: 700 Level Questions
09 Aug 2022, 02:03
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From the information, we can draw the matrix as
Red Car = 1/6
Not Red Car = 5/6
Model X = 5/13
Not Model X = 8/13
Taking an integer value that could satisfy all the above and ease calculation. For e.g. total cars = 78
Red Car = 13
Not Red Car = 65
Model X = 30
Not Model X = 48
Now the question wants us to find what can NOT be the probability of selecting a car, which is either of red color or X model or both
=> Out of a total of 78 cars, the probability of selecting a car, which is either of red color or X model or both is
(13 + 30 - Both Red and Model X) / Total Cars
=> (43 - Both Red and Model X) / 78
If we consider that there was no overlap (Both Red and Model X = 0) we would get the maximum probability of selecting a car with such a probability
=> the maximum probability = 43/78 ≈ 7/13
and considering the complete overlap i.e. Both Red and Model X = 13
=> the minimum probability = 30/78 = 5/13
The probability should fall between 5/13 and 43/78
Out of all the answer choices, only 3/8 does not fall within this range and hence should be the answer
IMHO Option A
Red Car = 1/6
Not Red Car = 5/6
Model X = 5/13
Not Model X = 8/13
Taking an integer value that could satisfy all the above and ease calculation. For e.g. total cars = 78
Red Car = 13
Not Red Car = 65
Model X = 30
Not Model X = 48
Now the question wants us to find what can NOT be the probability of selecting a car, which is either of red color or X model or both
=> Out of a total of 78 cars, the probability of selecting a car, which is either of red color or X model or both is
(13 + 30 - Both Red and Model X) / Total Cars
=> (43 - Both Red and Model X) / 78
If we consider that there was no overlap (Both Red and Model X = 0) we would get the maximum probability of selecting a car with such a probability
=> the maximum probability = 43/78 ≈ 7/13
and considering the complete overlap i.e. Both Red and Model X = 13
=> the minimum probability = 30/78 = 5/13
The probability should fall between 5/13 and 43/78
Out of all the answer choices, only 3/8 does not fall within this range and hence should be the answer
IMHO Option A
Updated on: 09 Aug 2022, 18:56
Originally posted by ThatDudeKnows on 09 Aug 2022, 07:09.
Last edited by ThatDudeKnows on 09 Aug 2022, 18:56, edited 1 time in total.
Last edited by ThatDudeKnows on 09 Aug 2022, 18:56, edited 1 time in total.
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Bunuel
The probability of selecting model X is 5/13, which is 38.something percent.
The probability of selecting model X or red or both cannot be lower than that.
3/8 = 37.5 percent
Answer choice A.
