Probablity Question Help (1 Viewer)

barbernator

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i don't think the answer is purely 4/7, because the question says if at least one gold coin is selected. this doesn't mean that the gold coin was selected first; it could have been selected second, and all we know is that at least one was chosen, so i reckon barbenator's answer is correct
wooo another one to join the ring :D
 

barbernator

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oh yes mr probability realise is in to help sort out :)
 

RealiseNothing

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This is actually very similar to a semi-famous probability question that goes something like this:

"If a family has two children, and it is known that atleast one of the children is a boy, what is the probability that the other child is also a boy?"

Basically there are 3 cases: BB, GB, and, BG.

I would think the same applies here, such that you can choose either GG, SG, or GS.
 

barbernator

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This is actually very similar to a semi-famous probability question that goes something like this:

"If a family has two children, and it is known that atleast one of the children is a boy, what is the probability that the other child is also a boy?"

Basically there are 3 cases: BB, GB, and, BG.

I would think the same applies here, such that you can choose either GG, SG, or GS.
I agree. http://math.stackexchange.com/quest...t-are-the-chances-if-one-of-the-children-is-a

either way, it is a great question!
 

Indoz

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Q10. a) There are 5 gold coins and 3 silver coins in a purse. Christine selects 2 of
these coins at random. Find the probability that:
i. She selects 2 gold coins.
ii. She selects 1 gold coins and 1 silver coin.
iii. She selects 2 gold coins if it is known that she selected at least I
gold coin.

Having trouble with (iii)
Any ideas?
so what were the answers?
 

jamesischool

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i'm guessing that it's accepted the possibilities are GG, GS and SG (all have at least 1 gold coin chosen). from there you'd find the probability of getting GG as a percentage of getting at least 1 gold?
so what were the answers?
 

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