M= {-6, -5, -4, -3, -2}
T= {-2, -1, 0, 1, 2, 3}
If an integer is to be randomly selected from set M above and an integer is to be randomly selected from set T above, what is the probability that the product of the two integers will be negative?
A. 0
B. 1/3
C. 2/5
D. 1/2
E. 3/5
Probability problem...need explanation plzz
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IMPORTANT: the number chosen from set M is ALWAYS negative.akpareek wrote:M= {-6, -5, -4, -3, -2}
T= {-2, -1, 0, 1, 2, 3}
If an integer is to be randomly selected from set M above and an integer is to be randomly selected from set T above, what is the probability that the product of the two integers will be negative?
A. 0
B. 1/3
C. 2/5
D. 1/2
E. 3/5
So, the only way to get a negative product is when the number chosen from set T is POSITIVE.
P(number chosen from set T is positive) = 3/6 = [spoiler]1/2 = D[/spoiler]
Cheers,
Brent
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HI BrentBrent@GMATPrepNow wrote:IMPORTANT: the number chosen from set M is ALWAYS negative.akpareek wrote:M= {-6, -5, -4, -3, -2}
T= {-2, -1, 0, 1, 2, 3}
If an integer is to be randomly selected from set M above and an integer is to be randomly selected from set T above, what is the probability that the product of the two integers will be negative?
A. 0
B. 1/3
C. 2/5
D. 1/2
E. 3/5
So, the only way to get a negative product is when the number chosen from set T is POSITIVE.
P(number chosen from set T is positive) = 3/6 = [spoiler]1/2 = D[/spoiler]
Cheers,
Brent
Cannot i solve this problem the following way?
P(that product of 2 integers is -ve) = 1 - P(that product of 2 integers is +ve)
= 1 - [ P(integer selected from set"M" is -ve) AND P(integer selected from set T is -ve)]
= 1 - [ (5/5) * (2/6)]
= 1 - (1/3)
= 2/3
Where am i getting this wrong?
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Hi madhusudhan237,
Set T contains a 0, so you ALSO have to factor in the possibility that the product of the two numbers will be 0 (and subtract that outcome as well). Your solution did not include that possibility.
GMAT assassins aren't born, they're made,
Rich
Set T contains a 0, so you ALSO have to factor in the possibility that the product of the two numbers will be 0 (and subtract that outcome as well). Your solution did not include that possibility.
GMAT assassins aren't born, they're made,
Rich