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In a group of 8 semifinalists, all but 2 will advance to the final rou
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22 May 2016, 13:46
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In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible? (A) 20 (B) 56 (C) 120 (D) 560 (E) 720
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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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22 May 2016, 19:26
Bunuel wrote: In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible?
(A) 20 (B) 56 (C) 120 (D) 560 (E) 720 Hi, there are two points to remember 1) Is it important here that how many go into finals... NO....what is important is HOW many get medals..3 finally these 3 can be any of the 8  \(8C3 = \frac{8!}{5!3!} = \frac{8*7*6}{3*2}=56\) 2) Is order important...NOwe are looking for groups only.. ans 56 B
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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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03 Jul 2017, 01:30
Palaksehgal3 wrote: As per the question, only 6 semifinalists made it to the 3rd round. So why is the answer not 6c3? Yes, but initial number is still 8. Do we know which 2 won't advance to the final? No. So, the size of the group we are selecting from is still 8. In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible?(A) 20 (B) 56 (C) 120 (D) 560 (E) 720 Intermediary step about "all but 2 will advance to the final round" is just to confuse us: any group of 3 is equally likely to win, so we can skip this part and directly calculate ways to choose 3 contestants out of 8: \(C3_8=56\). Answer: B.
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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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03 Jul 2017, 01:44
Palaksehgal3 wrote: Bunuel wrote: Palaksehgal3 wrote: As per the question, only 6 semifinalists made it to the 3rd round. So why is the answer not 6c3? Yes, but initial number is still 8. Do we know which 2 won't advance to the final? No. So, the size of the group we are selecting from is still 8. In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible?(A) 20 (B) 56 (C) 120 (D) 560 (E) 720 Intermediary step about "all but 2 will advance to the final round" is just to confuse us: any group of 3 is equally likely to win, so we can skip this part and directly calculate ways to choose 3 contestants out of 8: \(C3_8=56\). Answer: B. Makes sense. Thanks Bunuel I am having a hard time with probability and permutations. Could you please advise how to go about improving at it? Check the links below: Combinatorics Made Easy!Theory on CombinationsDS questions on CombinationsPS questions on CombinationsTough and tricky questions on CombinationsProbability Made Easy!Theory on probability problemsData Sufficiency Questions on ProbabilityProblem Solving Questions on ProbabilityTough Probability QuestionsHope it helps.
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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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09 Jun 2017, 09:11
For this problem we have to select 3 semifinalists out of 8 so \(8_C_3\) Answer B



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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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03 Jul 2017, 01:15
As per the question, only 6 semifinalists made it to the 3rd round. So why is the answer not 6c3?



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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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03 Jul 2017, 01:42
Bunuel wrote: Palaksehgal3 wrote: As per the question, only 6 semifinalists made it to the 3rd round. So why is the answer not 6c3? Yes, but initial number is still 8. Do we know which 2 won't advance to the final? No. So, the size of the group we are selecting from is still 8. In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible?(A) 20 (B) 56 (C) 120 (D) 560 (E) 720 Intermediary step about "all but 2 will advance to the final round" is just to confuse us: any group of 3 is equally likely to win, so we can skip this part and directly calculate ways to choose 3 contestants out of 8: \(C3_8=56\). Answer: B. Makes sense. Thanks Bunuel I am having a hard time with probability and permutations. Could you please advise how to go about improving at it?



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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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21 Jan 2020, 06:23
Bunuel wrote: Palaksehgal3 wrote: As per the question, only 6 semifinalists made it to the 3rd round. So why is the answer not 6c3? Yes, but initial number is still 8. Do we know which 2 won't advance to the final? No. So, the size of the group we are selecting from is still 8. In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible?(A) 20 (B) 56 (C) 120 (D) 560 (E) 720 Intermediary step about "all but 2 will advance to the final round" is just to confuse us: any group of 3 is equally likely to win, so we can skip this part and directly calculate ways to choose 3 contestants out of 8: \(C3_8=56\). Answer: B. Why is 8c6 * 6c3 wrong ? In this ,we are selecting 6 persons out of 8 as 2 will not advance to the final round. Posted from my mobile device



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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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25 Jan 2020, 09:04
Bunuel wrote: Palaksehgal3 wrote: As per the question, only 6 semifinalists made it to the 3rd round. So why is the answer not 6c3? Yes, but initial number is still 8. Do we know which 2 won't advance to the final? No. So, the size of the group we are selecting from is still 8. In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible?(A) 20 (B) 56 (C) 120 (D) 560 (E) 720 Intermediary step about "all but 2 will advance to the final round" is just to confuse us: any group of 3 is equally likely to win, so we can skip this part and directly calculate ways to choose 3 contestants out of 8: \(C3_8=56\). Answer: B. [color=#ff0000] why 8C6 x 6C3 is wrong??[/color]



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Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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25 Jan 2020, 18:15
aarushisingla wrote: Bunuel wrote: Palaksehgal3 wrote: As per the question, only 6 semifinalists made it to the 3rd round. So why is the answer not 6c3? Yes, but initial number is still 8. Do we know which 2 won't advance to the final? No. So, the size of the group we are selecting from is still 8. In a group of 8 semifinalists, all but 2 will advance to the final round. If in the final round only the top 3 will be awarded medals, then how many groups of medal winners are possible?(A) 20 (B) 56 (C) 120 (D) 560 (E) 720 Intermediary step about "all but 2 will advance to the final round" is just to confuse us: any group of 3 is equally likely to win, so we can skip this part and directly calculate ways to choose 3 contestants out of 8: \(C3_8=56\). Answer: B. Why is 8c6 * 6c3 wrong ? In this ,we are selecting 6 persons out of 8 as 2 will not advance to the final round. Posted from my mobile deviceYea, this is what I did as well. :/




Re: In a group of 8 semifinalists, all but 2 will advance to the final rou
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25 Jan 2020, 18:15






