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In a race with 10 competitors, the firstplace finisher receives a gol
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Updated on: 20 Jun 2011, 22:30
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In a race with 10 competitors, the firstplace finisher receives a gold medal, the secondplace finisher receives a silver medal, and the thirdplace finisher receives a bronze medal. If there are no ties, in how many different ways may these three medals be awarded? 35 120 720 840 604,800
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Originally posted by siddhans on 19 Jun 2011, 15:18.
Last edited by siddhans on 20 Jun 2011, 22:30, edited 1 time in total.



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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26 Jun 2011, 10:43
siddhans wrote: Explain in detail... When does order matter ? How do we know that? and when order of selection doesnt matter? I always get confused...
In a race with 10 competitors, the firstplace finisher receives a gold medal, the secondplace finisher receives a silver medal, and the thirdplace finisher receives a bronze medal. If there are no ties, in how many different ways may these three medals be awarded? 35 120 720 840 604,800 Here the order matters. Why? Say there are 3 competitors, A, B, C for 2 medals: Gold(G) & Silver(S) Winners can be: G S  A B B A A C C A B C C B "A" winning the Gold medal & B winning the silver is different from "B" winning the gold & "A" winning the silver. Thus both scenario should be considered. A B B A So, you choose 2 people out of 3 and rearrange them in 2! way. \(C^3_2*2!=6\) Likewise, if there are 10 people; you choose 3 winners first i.e. \(C^{10}_3\) And then rearrange those 3!. Total = \(C^{10}_3*3!=720\) ************************************* If someone says make 2 teams from 3 people A, B, C, then \(C^3_2\) suffices. Note: Having a team that contains A and B IS NO DIFFERENT FROM Having a team that contains B and A Thus, order won't matter there. ********************************
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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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19 Jun 2011, 19:10
Well in this case since there are 3 positions and they can be taken by 3 persons only ,so order matters over here .For gold there are 10 choices ,for silver 9 remain (one who got gold cannot be given silver) and for bronze 8 choices remain. So total possibilities=10*9*8
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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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26 Jun 2011, 10:29
If From 10 people, we need to pick 3 medal winners > Just picking hence no need of order
But in these 3 medal winners, gold, silver and bronze is unique> hence order matters so it is permutations
10P3 is answer = 10 x 9 x 8 = 720



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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26 Jun 2011, 11:55
we have 10 people and three medals.
so these three medals can be considered as three slots to fill.
one slot is Gold,one slot is Silver and last slot is Bronze.
Order matters here why, if we seat one person in one place that gives one arrangement and if we re arrange this it gives a different arrangement (eg  Person1 sitting in Gold slot vs Person sitting in Bronze slot  different arrangements. hence order matters).
So its permutations and number of arrangements = 10*9*8 = 720



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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27 Jun 2011, 06:39
I too get confused many times with order. good Question



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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27 Jun 2011, 10:49
siddhans wrote: Explain in detail... When does order matter ? How do we know that? and when order of selection doesnt matter? I always get confused...
In a race with 10 competitors, the firstplace finisher receives a gold medal, the secondplace finisher receives a silver medal, and the thirdplace finisher receives a bronze medal. If there are no ties, in how many different ways may these three medals be awarded? A 35 B 120 C 720 D 840 E 604,800
Total Competitors =10 ways of selecting the Gold medal winner = 10 ways (we can select anyone) ways of selecting the Silver medal winner = 9 ways (we can select anyone but not the Gold medal winner) ways of selecting the Bronze medal winner = 8 ways (we can select anyone but not the 2 winners already choosen) so total no of ways will be = 10 x 9 x 8 = 720 hope this helps......
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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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28 Jun 2011, 10:25
When I first read the topic, I thought GMAT Club was having some competition about solving MGMAT ps questions for 10 people and they were awarding medals. Then I read the post and thought, "why do these competition rules have numbers at the bottom?" *smacks head.



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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14 Oct 2011, 07:51
imerial wrote: When I first read the topic, I thought GMAT Club was having some competition about solving MGMAT ps questions for 10 people and they were awarding medals. Then I read the post and thought, "why do these competition rules have numbers at the bottom?" *smacks head. I thought the same.



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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21 Mar 2017, 15:36
don't fall into trap of using anagram grid: 10!/3!7!=120. this is wrong, because we are not looking in how many orders can the medals be distributed but we are looking for number of ways winners can get their medals, so simple permutation is fine
10!/7!=8*9*10=720



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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29 May 2017, 11:56
siddhans wrote: In a race with 10 competitors, the firstplace finisher receives a gold medal, the secondplace finisher receives a silver medal, and the thirdplace finisher receives a bronze medal. If there are no ties, in how many different ways may these three medals be awarded?
35 120 720 840 604,800 This problem can be solved in two ways. First realize that the number of ways to award a first place medal is 10 because there are 10 entrants. The total number of possibilities to award a second place medal is 9 because there are 9 remaining participants. Lastly, the total number of ways to award a third place medal is 8 because there are 8 remaining runners after the first two medals have been awarded. 10*9*8 = 720. Alternatively, using combinatorics, you can realize that there are 10! ways to arrange the 10 racers. But you've overcounted, so you need to remove the 7! racers who are all collectively "losers." Their order doesn't matter since they are in the group together. 10!/7! = 720.



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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12 Jun 2017, 00:31
the answer must be C , actually here the order does matter means whoever comes first will be awarded the gold and so on , so order matter . now we have 10*9*8=720 ways to choose for subsequent outcomes hence C



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Re: In a race with 10 competitors, the firstplace finisher receives a gol
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14 Jun 2017, 16:28
siddhans wrote: In a race with 10 competitors, the firstplace finisher receives a gold medal, the secondplace finisher receives a silver medal, and the thirdplace finisher receives a bronze medal. If there are no ties, in how many different ways may these three medals be awarded?
35 120 720 840 604,800 Since there are 10 competitors and three positions in which they can place, the number of ways the medals can be awarded is 10P3 = 10 x 9 x 8 = 720. Answer: C
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