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mydreammba
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Probability 06 Jan 2012, 07:26
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Can anyone please explain...

I thought the answer is 0.063, but its not correct....Please explain



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E
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blink005
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Probability Updated on: 07 Jan 2012, 01:28
Originally posted by blink005 on 06 Jan 2012, 07:40.
Last edited by blink005 on 07 Jan 2012, 01:28, edited 2 times in total.
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Are you sure it's "E"?

I think it's C
P(buying)=0.3
P(not buying)=0.7

P(2 buy candy)= 0.3*0.3*0.7=0.063

Let the three visitors be X, Y, and Z.
There are three ways that two visitors buy candies.
XY; YZ; ZX

Hence, required probability= 3*0.063= 0.189
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Probability 06 Jan 2012, 08:04
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blink005
Are you sure it's "E".

I think it's C
P(buying)=0.3
P(not buying)=0.7

P(2 buy candy)= 0.3*0.3*0.7=0.063

Let the three visitors be X, Y, and Z.
There are three ways that two visitors buy candies.
X,Y; YZ; ZX

Hence, require probability= 3*0.063= 0.189
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Yes the answer is E....and i think ur approach is correct
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shinbhu
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Probability 06 Jan 2012, 20:03
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Here's why,

RULE: In probability, if say three events that happen exclusively of eachother, you should always multiply the number of combinations of those events with the derived probability of one of those events (same probability for all).

2 people buy, 1 doesn't, so unit probability = (0.3)(0.3)(0.7) = 0.063

Now, we can have BBN, BNB, NBB (where N = no buy, B = buy)

So, we get 3 x 0.063 = 0.189 -> C
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Probability 07 Jan 2012, 04:06
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shinbhu
Here's why,

RULE: In probability, if say three events that happen exclusively of eachother, you should always multiply the number of combinations of those events with the derived probability of one of those events (same probability for all).

2 people buy, 1 doesn't, so unit probability = (0.3)(0.3)(0.7) = 0.063

Now, we can have BBN, BNB, NBB (where N = no buy, B = buy)

So, we get 3 x 0.063 = 0.189 -> C
Show more

Thanks dude......



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