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Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the

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Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the  [#permalink]

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New post 16 Sep 2015, 04:31
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

70% (00:45) correct 30% (00:38) wrong based on 120 sessions

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Re: Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the  [#permalink]

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New post 16 Sep 2015, 07:28
2
Answer is C

From statement 1 we get that a is: 7<=a<=12
Not sufficient

From statement 2, we know that a cannot be either 2, 7, 12 or 17 but not sufficient to assume a specific value of a.

Taking both, 7<a<=12
hence a>7
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Re: Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the  [#permalink]

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New post 16 Sep 2015, 08:06
longfellow wrote:
Answer is C

From statement 1 we get that a is: 7<=a<=12
Not sufficient

From statement 2, we know that a cannot be either 2, 7, 12 or 17 but not sufficient to assume a specific value of a.

Taking both, 7<a<=12
hence a>7



thought the same !!
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Re: Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the  [#permalink]

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New post 20 Sep 2015, 22:19
Bunuel wrote:
Set J consists of terms {2, 7, 12, 17, a}. Is a > 7?

(1) a is the median of set J
(2) Set J does not have a mode

Kudos for a correct solution.


VERITAS PREP OFFICIAL SOLUTION:

For most, statement 1 looks very sufficient, as if a is the “middle number” then it would go between 7 and 12 on the list {2, 7, a, 12, 17}. That would mean that on this chart, you’re at A, as statement 2 is pretty worthless on its own:

___D___

A_____B

___C___

___E___

You can very confidently eliminate B and probably E, too, but if you’re sitting on a “probable A,” you’ll want to consider one level above and one level below your answer on the chart. Why? Because if the answer is, indeed, trickier than your first-30-seconds-assessment, the options are that either:

*The statement you thought was sufficient was close, but there’s a little hiccup (you thought A, but it’s C)

*The statement you thought was not sufficient was actually really cleverly sufficient had you just worked a little harder to reveal it (you thought A, but it’s D)

This is what Veritas Prep’s Data Sufficiency book calls “The Reward System” – many questions are created to reward those examinees who dig deeper on an “obvious” answer via critical thinking, and to “punish” those who leap to judgement and fall for the sucker choice. If A is the sucker choice, the answer is almost always D or C, so you know what you have to do…check to make sure that statement 2 is not sufficient, and then check (often using statement 2) to make sure that you haven’t overlooked a unique situation that would show that statement 1 is actually not sufficient. And here, further review shows this:

If a = 7, a is still the median of the set, but 7 is NOT greater than 7, so that answer would be “no” – there’s a way that a is not greater than 7, so we actually need statement 2. If there is no mode, then a can’t be 7 (that would be a duplicate number, making 7 the mode). So the answer is C, and the Reward System thinking can help make sure you streamline your thought process to help you identify that. If you picked A you’re not alone – many do. But if you picked A and then considered the chart:

___D___

A_____B

___C___

___E___

You should have spent that extra 30 seconds making sure that the answer wasn’t C or D, and that may have given you the opportunity to reap the rewards of thinking critically via the Data Sufficiency question structure.

So remember – merely knowing what the answer choices are is an elementary step in Data Sufficiency mastery; learning to use those to your advantage via the Reward System will help you avoid trap answers and stake your place among those being rewarded.
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Re: Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the  [#permalink]

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New post 26 Jan 2017, 23:09
This is one of those quant questions for which you don't need to write on scrap paper but just think critically, click the answer and move on. Doing such questions would also help get away with bad habbit of directly jumping on solving the question.

stmt-1: If a is the median of set J, then it can be anything from 7 to 12, inclusive. so this a=7 or a>7. insuff.

stmt-2: Right away looking at B sees that it helps stmt-1 to be sufficient because it removes a=7 as a possibility because if there is no mode, it means no number in the set can repeat. But be aware to always check the sufficiency of a stmt alone itself whenever that stmt make the other sufficient. this helps get away C-Trap.
obviously a can be any number different from those given in set j. hence insufficient.

Answer is C.

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Re: Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the  [#permalink]

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New post 26 Jan 2017, 23:34
Bunuel wrote:
Set J consists of terms {2, 7, 12, 17, a}. Is a > 7?

(1) a is the median of set J
(2) Set J does not have a mode

Kudos for a correct solution.



1. a is a median , so A can be equal to or greater than 7 ..so insuff
2. A can be 1 ,3 11 etc ..so in suff

combining 1 and 2 we will get a cant be equal to 7 ...only values a can have is greater than 7.
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Re: Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the  [#permalink]

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Re: Set J consists of terms {2, 7, 12, 17, a}. Is a > 7? (1) a is the &nbs [#permalink] 22 Aug 2018, 09:35
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