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This year, x people won an Olympic medal for water competitions. One [#permalink]
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16 Sep 2015, 07:16
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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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16 Sep 2015, 07:40
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Bunuel wrote: This year, x people won an Olympic medal for water competitions. Onethird of the winners earned a medal for swimming and onefourth of those who earned a medal for swimming also earned a medal for diving. How many people won an Olympic medal for water competitions but did not both receive a medal for swimming and a medal for diving?
(A) 11x/12 (B) 7x/12 (C) 5x/12 (D) 6x/7 (E) x/7
Kudos for a correct solution. Solution : Medals for swimming = x/3 Medals won for diving by those who also won for swimming = 1/4(x/3) = x/12. Required = x  x/12 = 11x/12 Option A



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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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17 Sep 2015, 15:26
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Bunuel wrote: This year, x people won an Olympic medal for water competitions. Onethird of the winners earned a medal for swimming and onefourth of those who earned a medal for swimming also earned a medal for diving. How many people won an Olympic medal for water competitions but did not both receive a medal for swimming and a medal for diving?
(A) 11x/12 (B) 7x/12 (C) 5x/12 (D) 6x/7 (E) x/7
Kudos for a correct solution. Everyone won at least one medal. Also, the number of people who won medal for both diving and swimming is (x/3)*1/4 = x/12 Now, (AuB)  (AnB) = complement of (AnB) here AuB = x AnB = x/12 The number of people who won single medal(or compliment of AnB) is xx/12 =11x/12 Answer:A



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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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18 Sep 2015, 04:31
Bunuel wrote: This year, x people won an Olympic medal for water competitions. Onethird of the winners earned a medal for swimming and onefourth of those who earned a medal for swimming also earned a medal for diving. How many people won an Olympic medal for water competitions but did not both receive a medal for swimming and a medal for diving?
(A) 11x/12 (B) 7x/12 (C) 5x/12 (D) 6x/7 (E) x/7
Kudos for a correct solution. medal for swimming = x/3 medal for Diving = (1/4)(x/3) = x/12 People With Medal for Swimming ONLY = (x/3)  (1/4)(x/3) = (3/4)(x/3) = x/4 Medal for Diving ONLY = Total  People with medal for Swimming = x  (x/3) = 2x/3 Total People with One Medal ONLY = 2x/3 + x/4 = 11x/12 Answer: Option A
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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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20 Sep 2015, 08:58
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Bunuel wrote: This year, x people won an Olympic medal for water competitions. Onethird of the winners earned a medal for swimming and onefourth of those who earned a medal for swimming also earned a medal for diving. How many people won an Olympic medal for water competitions but did not both receive a medal for swimming and a medal for diving?
(A) 11x/12 (B) 7x/12 (C) 5x/12 (D) 6x/7 (E) x/7
Kudos for a correct solution. VERITAS PREP OFFICIAL SOLUTION:Let’s work on a Venn diagram and fill in what we do know – an important first step as many of these problems come down in large part to “getting organized”. We know there will be some medal winners who swam but did not dive, some who dove but did not swim, and some who swam AND dove. “x” here will be at the top of our Venn because it is the total for ALL PARTS of the Venn. That is, all three categories will sum to x. x/3 represents the 1/3 of the total (“x”) who swam, including those who swam only AND those who swam and dove. We can make up a variable, let’s say “y,” to represent the total number of divers. The key to understanding this question lies in the last sentence and the phrase “not both.” We need to know the people who ONLY swam but did NOT dive, and the people who ONLY dove but did NOT swim. I made up variables for these two groups: “a” and “z.” Let’s use the answer choices to our advantage! Since they have the denominators of 12 and 7, let’s use one of those and work backwards! 12 appears more often, so we can start there. If x = 12, there are 12/3 = 4 swimmers total, (12/3)/4 = 1 of whom swam and dove. That means a = 3. If 4 people swam, then 124 = 8 dove, so z = 8. The two categories we’re looking for (a + z) are 3 + 8 = 11. We are looking for an answer choice that gives us 11 when x = 12. The answer is (A).
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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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20 Sep 2015, 11:50
Hi All, This question can be solved by TESTing VALUES (and taking a few notes). We're told that X people won a medal for water competitions. Of those X people, 1/3 won a medal for swimming; of those who won a medal for SWIMMING, 1/4 also won a medal for diving. The common denominator between 1/3 and 1/4 is 12, so let's TEST X = 12.... X = 12 medal winners (1/3)(12) = 4 won a medal for swimming (1/4)(4) = 1 of the swimming winners ALSO won a medal for diving We're asked how many of the X people did NOT win a medal for BOTH swimming and diving. Since there were 12 people, and only 1 won BOTH medals, the other 11 won JUST ONE medal  thus, the answer to the question is 11 (when X = 12). The answers are written in such a way that you don't have to do much math to find the correct answer. Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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23 Apr 2016, 04:24
Bunuel wrote: Bunuel wrote: This year, x people won an Olympic medal for water competitions. Onethird of the winners earned a medal for swimming and onefourth of those who earned a medal for swimming also earned a medal for diving. How many people won an Olympic medal for water competitions but did not both receive a medal for swimming and a medal for diving?
(A) 11x/12 (B) 7x/12 (C) 5x/12 (D) 6x/7 (E) x/7
Kudos for a correct solution. VERITAS PREP OFFICIAL SOLUTION:Let’s work on a Venn diagram and fill in what we do know – an important first step as many of these problems come down in large part to “getting organized”. We know there will be some medal winners who swam but did not dive, some who dove but did not swim, and some who swam AND dove. “x” here will be at the top of our Venn because it is the total for ALL PARTS of the Venn. That is, all three categories will sum to x. x/3 represents the 1/3 of the total (“x”) who swam, including those who swam only AND those who swam and dove. We can make up a variable, let’s say “y,” to represent the total number of divers. The key to understanding this question lies in the last sentence and the phrase “not both.” We need to know the people who ONLY swam but did NOT dive, and the people who ONLY dove but did NOT swim. I made up variables for these two groups: “a” and “z.” Let’s use the answer choices to our advantage! Since they have the denominators of 12 and 7, let’s use one of those and work backwards! 12 appears more often, so we can start there. If x = 12, there are 12/3 = 4 swimmers total, (12/3)/4 = 1 of whom swam and dove. That means a = 3. If 4 people swam, then 124 = 8 dove, so z = 8. The two categories we’re looking for (a + z) are 3 + 8 = 11. We are looking for an answer choice that gives us 11 when x = 12. The answer is (A).In the last part, When only ppl eho dove has to be found out, why havent we done 81 to get ppl who dove only.Because for ppl who Swam only we did SwamBoth+Swam only, so why not Dove only=Total SwamBoth. Bunuel kindly clear my doubt here.



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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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24 Apr 2016, 04:09
89renegade wrote: Bunuel wrote: Bunuel wrote: This year, x people won an Olympic medal for water competitions. Onethird of the winners earned a medal for swimming and onefourth of those who earned a medal for swimming also earned a medal for diving. How many people won an Olympic medal for water competitions but did not both receive a medal for swimming and a medal for diving?
(A) 11x/12 (B) 7x/12 (C) 5x/12 (D) 6x/7 (E) x/7
Kudos for a correct solution. VERITAS PREP OFFICIAL SOLUTION:Let’s work on a Venn diagram and fill in what we do know – an important first step as many of these problems come down in large part to “getting organized”. We know there will be some medal winners who swam but did not dive, some who dove but did not swim, and some who swam AND dove. “x” here will be at the top of our Venn because it is the total for ALL PARTS of the Venn. That is, all three categories will sum to x. x/3 represents the 1/3 of the total (“x”) who swam, including those who swam only AND those who swam and dove. We can make up a variable, let’s say “y,” to represent the total number of divers. The key to understanding this question lies in the last sentence and the phrase “not both.” We need to know the people who ONLY swam but did NOT dive, and the people who ONLY dove but did NOT swim. I made up variables for these two groups: “a” and “z.” Let’s use the answer choices to our advantage! Since they have the denominators of 12 and 7, let’s use one of those and work backwards! 12 appears more often, so we can start there. If x = 12, there are 12/3 = 4 swimmers total, (12/3)/4 = 1 of whom swam and dove. That means a = 3. If 4 people swam, then 124 = 8 dove, so z = 8. The two categories we’re looking for (a + z) are 3 + 8 = 11. We are looking for an answer choice that gives us 11 when x = 12. The answer is (A).In the last part, When only ppl eho dove has to be found out, why havent we done 81 to get ppl who dove only.Because for ppl who Swam only we did SwamBoth+Swam only, so why not Dove only=Total SwamBoth. Bunuel kindly clear my doubt here. Total = x = 12 Swam only = a = 3 Both swam and dove = x/12 = 1 Dove only = z = Total  Swam only  Both = 12  3  1 = 8.
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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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04 Sep 2017, 11:17
Total= x Swimming= x/3 Both = x/12 Diving= y x= x/3+y x/12 x= 3x/4 Answer would be: x/4+2x/3= 11x/12 I got the answer but is this the correct way?
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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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27 Nov 2017, 19:18
where's the neither part in the formula? can any1 tell me? the part " people who neither won medal for swimming nor won medal for diving" . I saw many solutions omit this but I don't know why.



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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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27 Nov 2017, 21:02



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Re: This year, x people won an Olympic medal for water competitions. One [#permalink]
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27 Nov 2017, 21:14
Bunuel wrote: lichting wrote: where's the neither part in the formula? can any1 tell me? the part " people who neither won medal for swimming nor won medal for diving" . I saw many solutions omit this but I don't know why. Here the sample is those who won a medal: x people won an Olympic medal for water competitions. Thank you a lot!! my mistake




Re: This year, x people won an Olympic medal for water competitions. One
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