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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. 49/4 Explanation: The original set was (2,3,5,7), Its median was 4. The median of the new set is 4*1.25 =5 Thus, the number added cannot be less than 5.
The correct answer is A. Can someone explain? I may be misreading the question, but it does not say the set consists of all the signle digit prime numbers with no repeats. From the way it is worded: A number was added to a set that consists of single digit prime integers, couldn't that mean that {2,2,2,2,2} is an example of one such set, so is {7,7,7}?
I reasoned the lowest possible current median is 2 (if all 2's) and the highest possible current median is 7 (set of all 7's) so the new median would be between 2.5 and 8.75 (it does not say the number added had to be an integer) ...is this just a poorly worded question or am I reading too mcuh into it? Thanks
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Re: m22 #15 [#permalink]
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28 Sep 2010, 04:05
It can't be all 2's or anything because it means that the set has "all the 1 digit prime nos." At least that is how I immediately interpreted it. I'd suggest don't go into semantics it can get confusing when it isn't.
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Re: m22 #15 [#permalink]
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18 Mar 2014, 04:24
Michmax3 wrote: If after a number was added to a set consisting of all 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)49/4 Explanation: The original set was (2,3,5,7), Its median was 4. The median of the new set is 4*1.25 =5 [b]Thus, the number added cannot be less than 5.
[/b]
Hi Bunuel,
Got the above question today....I guessed this one and moved on
Can you elaborate the part in red...
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Re: m22 #15 [#permalink]
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18 Mar 2014, 05:15
WoundedTiger wrote: Michmax3 wrote: If after a number was added to a set consisting of all 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)49/4 Explanation: The original set was (2,3,5,7), Its median was 4. The median of the new set is 4*1.25 =5 [b]Thus, the number added cannot be less than 5.
[/b]
Hi Bunuel,
Got the above question today....I guessed this one and moved on
Can you elaborate the part in red...For the median of {2, 3, 5, 7, x} to be 5 (5 to be the middle term), x must be greater than or equal to 5. If x is less than 5, the median would also be less than 5. Hope it's clear.
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Re: m22 #15 [#permalink]
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11 Jun 2014, 22:02
Got this question today and was confused that the stem does not limit the possibility of repeating the numbers in set, so median of the original set is not limited to 3+5=4. Do I understand the stem wrong?



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12 Jun 2014, 04:41



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Re: m22 #15 [#permalink]
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17 Jul 2014, 02:31
Although the answer is evident...the question,according to me, is not correct How can there ever be multiple answer to this question The set is defined as 2,3,5,7...median 4 New set..2,3,5,7....median is 5 The new number has to be 8..which part did I misinterpret??
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Re: m22 #15 [#permalink]
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17 Jul 2014, 07:31
JusTLucK04 wrote: Although the answer is evident...the question,according to me, is not correct
How can there ever be multiple answer to this question
The set is defined as 2,3,5,7...median 4 New set..2,3,5,7....median is 5
The new number has to be 8..which part did I misinterpret?? Check here: m22101817.html#p1345782For the median of {2, 3, 5, 7, x} to be 5 (5 to be the middle term), x must be greater than or equal to 5. If x is less than 5, the median would also be less than 5. Old set: {2, 3, 5, 7}. New set: {2, 3, 5, 7, x}. x must greater than or equal to 5, for the median to be 5. For example, if x=7.7, then the set is {2, 3, 5, 7, 7.7} > median = 5. Hope it's clear.
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Re: m22 #15 [#permalink]
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17 Jul 2014, 08:16
Bunuel wrote: JusTLucK04 wrote: Although the answer is evident...the question,according to me, is not correct
How can there ever be multiple answer to this question
The set is defined as 2,3,5,7...median 4 New set..2,3,5,7....median is 5
The new number has to be 8..which part did I misinterpret?? Check here: m22101817.html#p1345782For the median of {2, 3, 5, 7, x} to be 5 (5 to be the middle term), x must be greater than or equal to 5. If x is less than 5, the median would also be less than 5. Old set: {2, 3, 5, 7}. New set: {2, 3, 5, 7, x}. x must greater than or equal to 5, for the median to be 5. For example, if x=7.7, then the set is {2, 3, 5, 7, 7.7} > median = 5. Hope it's clear. I messed up this with average..noob me
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