explanation after OA
mgmatps2
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sudhir3127
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i am not happy with the way MGMAT has drafted this question... it wouldbe gr8 if stacey can help us understand it the way Mgmat wants it to be conveyed.. for me there are 2 answers...stubbornp wrote:please explain
one :
Probability of a non-nickel on first pick = (5 pennies + 4 dimes) / 15 coins = 3/5
Probability of a non-nickel on second pick = (8 non-nickel coins) / 14 coins = 4/7
thus its 3/5*4/7 = 12/35
second:
if this the Question is asking the probability of picking any combination other than NN.
Prob of NN = 6/15 * 5/14 = 1/7
Prob of not NN = 1- 1/7 = 6/7
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stubbornp
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sudhir3127 wrote:i am not happy with the way MGMAT has drafted this question... it wouldbe gr8 if stacey can help us understand it the way Mgmat wants it to be conveyed.. for me there are 2 answers...stubbornp wrote:please explain
one :
Probability of a non-nickel on first pick = (5 pennies + 4 dimes) / 15 coins = 3/5
Probability of a non-nickel on second pick = (8 non-nickel coins) / 14 coins = 4/7
thus its 3/5*4/7 = 12/35
second:
if this the Question is asking the probability of picking any combination other than NN.
Prob of NN = 6/15 * 5/14 = 1/7
Prob of not NN = 1- 1/7 = 6/7
Exactly sudhir,I am confused due to same reason.....
