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Re M2215
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16 Sep 2014, 01:16



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Re: M2215
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01 Jul 2015, 19:07
It´s not clear that the set has all 4 onedigit integers that are prime. One may understand that all items in the set are one digit integers (which would give you {2,3} or {3,5} or {2,3,5}.... just the way it´s written there is room for misunderstanding...



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michaelyb wrote: It´s not clear that the set has all 4 onedigit integers that are prime. One may understand that all items in the set are one digit integers (which would give you {2,3} or {3,5} or {2,3,5}.... just the way it´s written there is room for misunderstanding... Also, nowhere is it mentioned that all of them are positive.



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Re: M2215
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31 Oct 2015, 04:00



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Re: M2215
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07 Mar 2017, 04:29
hi Brunel how can you pick these numbers.For example if set is 2,3,5 then median is 3.after adding x median will become 3.75 so as per your statement number can't be less than 3.75
kindly clear where I am going wrong in my understanding



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Re: M2215
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07 Mar 2017, 05:02
sidagar wrote: hi Brunel how can you pick these numbers.For example if set is 2,3,5 then median is 3.after adding x median will become 3.75 so as per your statement number can't be less than 3.75
kindly clear where I am going wrong in my understanding The question says that the set consists of singledigit prime integers. There are four single digit primes: 2, 3, 5, and 7. So, the set is {2, 3, 5, 7} not {2, 3, 5}
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Re M2215
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04 Sep 2017, 11:22
I think this is a poorquality question. It says all distinct one digit prime numbers, however it can be unclear. I understood it as ALL the numbers in the set were distinict prime digits, not that they set included ALL the prime single digits



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Re: M2215
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06 Nov 2017, 06:10
Bunuel wrote: the number added cannot be less than 5. Hello Bunuel, can you please explain this in more detail? Would be happy to understand this.



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since the new median is 5, all options except B are wrong....????
in other words, if the question mentioned that the median grew by atleast 35%, A would be the answer.



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15 Nov 2017, 23:18
sevenplusplus wrote: If after a number was added to a set consisting of all distinct onedigit prime integers, the median of the set grew by 25%, which of the following cannot be the value of the number added?
A. 4.8 B. 5.0 C. \(\sqrt{29}\) D. 7.7 E. \(\frac{49}{4}\)
The original set was \(\{2, 3, 5, 7\}\). Its median was \(\frac{3 + 5}{2} = 4\). The median of the new set \(= 4*1.25 = 5\). Thus, the number added cannot be less than 5.
Answer: A
since the new median is 5, all options except B are wrong....????
in other words, if the question mentioned that the median grew by atleast 35%, A would be the answer. You are wrong. The original set = {2, 3, 5, 7}. The original median = 4. B. New number = 5; New set = {2, 3, 5, 5, 7}. New median = 5. C. New number = \(\sqrt{29}\); New set = 2, 3, 5, \(\sqrt{29}\), 7}. New median = 5. D. New number = 7.7; New set = {2, 3, 5, 7, 7.7}. New median = 5. E. New number = \(\frac{49}{4}\); New set = {2, 3, 5, 7, 49/4}. New median = 5.
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Re: M2215
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16 Nov 2017, 08:07
Bunuel wrote: sevenplusplus wrote: If after a number was added to a set consisting of all distinct onedigit prime integers, the median of the set grew by 25%, which of the following cannot be the value of the number added?
A. 4.8 B. 5.0 C. \(\sqrt{29}\) D. 7.7 E. \(\frac{49}{4}\)
The original set was \(\{2, 3, 5, 7\}\). Its median was \(\frac{3 + 5}{2} = 4\). The median of the new set \(= 4*1.25 = 5\). Thus, the number added cannot be less than 5.
Answer: A
since the new median is 5, all options except B are wrong....????
in other words, if the question mentioned that the median grew by atleast 35%, A would be the answer. You are wrong. The original set = {2, 3, 5, 7}. The original median = 4. B. New number = 5; New set = {2, 3, 5, 5, 7}. New median = 5. C. New number = \(\sqrt{29}\); New set = 2, 3, 5, \(\sqrt{29}\), 7}. New median = 5. D. New number = 7.7; New set = {2, 3, 5, 7, 7.7}. New median = 5. E. New number = \(\frac{49}{4}\); New set = {2, 3, 5, 7, 49/4}. New median = 5. Thanks. That clarifies. Sent from my iPhone using GMAT Club Forum mobile app



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Re: M2215
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19 Apr 2018, 11:24
michaelyb wrote: It´s not clear that the set has all 4 onedigit integers that are prime. One may understand that all items in the set are one digit integers (which would give you {2,3} or {3,5} or {2,3,5}.... just the way it´s written there is room for misunderstanding... Hi Bunuel, I agree with michaelyb. It is possible to revise the question? "If after a number was added to a set consisting entirely of all the distinct onedigit prime integers, the median of the set grew by 25%, which of the following cannot be the value of the number added?" Thank you.



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In my opionion the question is absolutely clear. No revision needed... "...set consisting of all distinct onedigit prime integers..." all onedigit primes (2,3,5,7) and no other integers.










