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Re: D0123 [#permalink]
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20 Aug 2017, 10:57
Indeed a high quality question that tests our skills of understanding prime numbers , reciprocals and divisibility. Though I am not qualified enough to pass any comment or remark on any question, but one thing I am sure is that almost all the questions of Bunuel are truly excellent... Sent from my Lenovo TAB S850LC using GMAT Club Forum mobile app



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Re: D0123 [#permalink]
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21 Aug 2017, 03:43



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Re: D0123 [#permalink]
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10 Nov 2017, 14:50
I can certainly see the logic in the explanation with this question, but I answered E. My basis for E is that all the terms could be 1/5 in which case the median is 1/5. My understanding of the wording of the question is the median has to be less than 1/5 to give a hard yes, but if you can have 1/5 as well as 1/2 and 7/20 as answers for #2, there is no clear yes or no. Am I overlooking something on this one?



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Re: D0123 [#permalink]
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11 Nov 2017, 01:28
zflodeen wrote: I can certainly see the logic in the explanation with this question, but I answered E. My basis for E is that all the terms could be 1/5 in which case the median is 1/5. My understanding of the wording of the question is the median has to be less than 1/5 to give a hard yes, but if you can have 1/5 as well as 1/2 and 7/20 as answers for #2, there is no clear yes or no. Am I overlooking something on this one? In a Yes/No Data Sufficiency questions, statement(s) is sufficient if the answer is “always yes” or “always no” while a statement(s) is insufficient if the answer is "sometimes yes" and "sometimes no". The question asks: is the median of the list less than 1/5? From (2) the median could be 1/2, 1/5 or 7/20. None of the possible values is less than 1/5. So, we have a definite NO answer to the question for all three possible values of the median. Sufficient. Hope it's clear.
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Re: D0123 [#permalink]
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11 Nov 2017, 10:12
Thank you Bunuel! That helps to clear up my thinking. I had a lapse in my brain and forgot that 1/2 is greater than 1/5. Thanks again!



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Re: D0123 [#permalink]
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10 Apr 2018, 12:19
Hello Bunuel 
As per choice B  "The product of any two term of the list is terminating decimal". now the list is of 10 numbers and consists of 1/2 and 1/5. So any two term can be 1/2 and 1/2 also right ???. I was confused about this while answering. Shouldn't the choice be  "The product of any two distinct term of the list is terminating decimal".
Kindly explain so that I can clear my concept.



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Re: D0123 [#permalink]
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10 Apr 2018, 12:38



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Re: D0123 [#permalink]
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10 Apr 2018, 13:36
My Bad  to get a terminating decimal  the denominator needs to be in the form of 2(power n) * 5 (power  n) . N can always be 0 as well. Time pressure  I am sorry.



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Re D0123 [#permalink]
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01 May 2018, 19:38
I think this is a highquality question and I agree with explanation. The Statement (2) is sufficient but the reason for sufficiency needs to be explained better because 1/8,1/10,1/4 and so on can also be in the set. But median or any of these values will continue to be lesser than 1/5. So the main reason we chose 1/2 & 1/5 is because they have the highest value that gives terminating decimals when multiplied. PS: Give me kudos if you see fit



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Re: D0123 [#permalink]
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01 May 2018, 20:58



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Re: D0123 [#permalink]
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02 May 2018, 03:43
Bunuel wrote: kittyman wrote: I think this is a highquality question and I agree with explanation. The Statement (2) is sufficient but the reason for sufficiency needs to be explained better because 1/8,1/10,1/4 and so on can also be in the set. But median or any of these values will continue to be lesser than 1/5. So the main reason we chose 1/2 & 1/5 is because they have the highest value that gives terminating decimals when multiplied. PS: Give me kudos if you see fit That's not correct. 1/8, 1/10 and 1/4 cannot be in the set because we are told that the set consists of 10 terms, each of which is a reciprocal of a prime number. 8, 10 and 4 are not primes. Understood Thanks Sent from my Moto G (4) using GMAT Club Forum mobile app



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Re D0123 [#permalink]
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20 Jun 2018, 07:09
I think this is a highquality question and I agree with explanation.



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Re: D0123 [#permalink]
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04 Jul 2018, 20:09
Why only 1/2 and 1/5 for statement two? It can also be 1/3, 1/7, 1/11 etc., right?
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Re: D0123 [#permalink]
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04 Jul 2018, 20:17
Manick9 wrote: Why only 1/2 and 1/5 for statement two? It can also be 1/3, 1/7, 1/11 etc., right? No. If there are reciprocals of other primes than 2 and 5, then the product of ANY two terms of the list won't be a terminating decimal. For example, if the list is {1/2, 1/2, 1/2, 1/2, 1/2, 1/2, 1/5, 1/5, 1/5, 1/3}, then no pair with 1/3 will produce the product which is a terminating decimal: 1/2*1/3 = 1/6 = 0.1666666.... and 1/5*1/6 = 0.0333333............... (reduced fraction to be terminating its denominator must have only 2's and/or 5 in it).
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Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
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Re: D0123 [#permalink]
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04 Jul 2018, 20:32
Thanks Bunuel! I didn't understand the definition of terminating decimal clearly at first. I got it confused with recurring decimal.
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