Can someone help solve this?
A hand purse contains 6 nickels, 5 pennies and 4 dimes. What is the probability of picking a coin other than a nickel twice in a row if the first coin picked is not put back?
Choices are:
8/25
12/35
13/35
9/25
17/25
And can you please tell me what level difficulty this would be considered because if this is considered easy... I might be in trouble..
Thanks!
Probability
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- beeparoo
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I am having difficulty with the possible AMBIGUITY of this Probability problem...
My interpretation of the Q, when it asks, "What is the probability of picking a coin other than a nickel twice in a row" is to also consider the possibility of picking a nickel ONCE during the two picks.
In summary, the picks could be:
(non-nickel, non-nickel)
(non-nickel, nickel)
(nickel, non-nickel)
But NOT (nickel, nickel)
I always have the most difficulty understanding what the question is asking for Probability-type questions. ARGH!!
Does anyone else have this problem too??
My interpretation of the Q, when it asks, "What is the probability of picking a coin other than a nickel twice in a row" is to also consider the possibility of picking a nickel ONCE during the two picks.
In summary, the picks could be:
(non-nickel, non-nickel)
(non-nickel, nickel)
(nickel, non-nickel)
But NOT (nickel, nickel)
I always have the most difficulty understanding what the question is asking for Probability-type questions. ARGH!!
Does anyone else have this problem too??
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- Master | Next Rank: 500 Posts
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GMAT will never come up with something ambiguous. Best approach to these questions is not to think that they are trying to confuse you
A hand purse contains 6 nickels, 5 pennies and 4 dimes. What is the probability of picking a non-nickel coin twice in a row if the first coin picked is not put back?
This can be rephrased as -A hand purse contains 6 nickels, 5 pennies and 4 dimes. What is the probability of picking a coin other than a nickel twice in a row if the first coin picked is not put back?
A hand purse contains 6 nickels, 5 pennies and 4 dimes. What is the probability of picking a non-nickel coin twice in a row if the first coin picked is not put back?
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- Master | Next Rank: 500 Posts
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beeparoo - you are not the only one getting confused by this problem
https://www.beatthegmat.com/a-hand-purse ... 12267.html
https://www.beatthegmat.com/a-hand-purse ... 12267.html