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If Jessica rolls a die, what is the probability of getting
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Updated on: 02 Oct 2012, 02:54
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80% (00:10) correct 20% (00:22) wrong based on 24 sessions
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If Jessica rolls a die, what is the probability of getting at least a "3"? Answer to this question is 2/3
but i think it should be 1/6
pls suggest whether i am right or wrong
Originally posted by Archit143 on 02 Oct 2012, 02:48.
Last edited by Bunuel on 02 Oct 2012, 02:54, edited 1 time in total.
Renamed the topic and edited the question.



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Re: If Jessica rolls a die, what is the probability of getting
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17 Jun 2015, 04:45
yamshi06 wrote: i approached like this , not getting a 3=5/6
atleast=15\6 = 1/6
pls explain what is wrong in the approach?? Probability = Favorable Outcomes / Total OutcomesA Die has 6 faces numbered from 1 through 6 i.e. Total Out comes = 6 Favorable outcomes = Numbers atleast 3 = numbers greater than or equal to 3 i.e. {3, 4, 5, 6} = 4 i.e. Probability = 4/6 = 2/3ALTERNATIVELYProbability = 1 (Unfavorable Outcomes / Total OutcomesUnfavorable outcomes = Numbers less than 3 = i.e. {1, 2} = 2 i.e. Probability = 1 (2/6) = 1(1/3) = 2/3I hope it clears your doubt!
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Re: If Jessica rolls a die, what is the probability of getting
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02 Oct 2012, 02:56
Archit143 wrote: If Jessica rolls a die, what is the probability of getting at least a "3"? Answer to this question is 2/3
but i think it should be 1/6
pls suggest whether i am right or wrong Favorable event would be if she gets 3, 4, 5, or 6 (at least 3), so four outcomes out of 6: P= favorable/total=4/6=2/3. Hope it's clear.
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Re: If Jessica rolls a die, what is the probability of getting
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02 Oct 2012, 03:03
Atleat 3 means 3 or more then 3 so outcome will be 3 4 5 6
probability of getting 3 is 1/6 so getting atleast 3 will be 1/6*1/6*1/6*1/6



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Re: If Jessica rolls a die, what is the probability of getting
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02 Oct 2012, 04:04
I have solved in this way.... probabilty of geting atleast 3.. suppose probability of geting 1 and 2..is ..1/6+1/6..2/6=1/3.. so probability of geting atleast 3 is...1probability of geting 1 and 2..we l get probabilty of geting atleast 3..rite? so 11/3=2/3..
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Re: If Jessica rolls a die, what is the probability of getting
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02 Oct 2012, 05:26
yes this approach is also rit
The probability of each outcome is 1/6. The probability of getting at least a "3" is:
1/6+1/6+ 1/6 +1/6 = 2/3 or what you mentioned
probability of not getting atleast 3
1 (1/6 + 1/6) = 2/3
both methods are fine



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Re: If Jessica rolls a die, what is the probability of getting
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17 Jun 2015, 04:32
i approached like this , not getting a 3=5/6 atleast=15\6 = 1/6 pls explain what is wrong in the approach??
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Re: If Jessica rolls a die, what is the probability of getting
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17 Jun 2015, 04:47
yamshi06 wrote: i approached like this , not getting a 3=5/6
atleast=15\6 = 1/6
pls explain what is wrong in the approach?? Please Note "If you subtract the probability of NOT getting 3 from 1 then you will get Probability of getting 3"whereas the question demand the probability of getting ATLEAST3
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Re: If Jessica rolls a die, what is the probability of getting
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17 Jun 2015, 05:12
we mainly do like dis, P(at least one success) = 1 – P(no success) i missing something in this concept plsd explain??
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Re: If Jessica rolls a die, what is the probability of getting
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17 Jun 2015, 05:32
yamshi06 wrote: we mainly do like dis, P(at least one success) = 1 – P(no success)
i missing something in this concept plsd explain?? You are getting it Right in this context Yashmi P(at least one success) = 1 – P(no success) is CORRECT But Probability of buying atleast 2 apples will NOT be same as (1probability of buying NO apple)You must Understand that Probability of buying atleast 2 apples will be equal to (1probability of NOT buying 2 or more apple)
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Re: If Jessica rolls a die, what is the probability of getting
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