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A pair of prime numbers that can be expressed in the form {p 10 Jul 2014, 17:06
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Difficulty:

25% (medium)

Question Stats:

73% (01:20) correct 27% (01:23) wrong based on 552 sessions

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A pair of prime numbers that can be expressed in the form {p, (p + 6)} is defined as a pair of “sexy primes.” A “sexy triplet” is a group of three primes that can be expressed in the form {p, (p + 6), (p + 12)}. All of the following prime numbers are the middle term of a sexy triplet EXCEPT

(A) 11
(B) 13
(C) 17
(D) 19
(E) 23

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D
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BrentGMATPrepNow
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A pair of prime numbers that can be expressed in the form {p 19 Sep 2021, 12:40
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A pair of prime numbers that can be expressed in the form {p, (p + 6)} is defined as a pair of “sexy primes.” A “sexy triplet” is a group of three primes that can be expressed in the form {p, (p + 6), (p + 12)}. All of the following prime numbers are the middle term of a sexy triplet EXCEPT

(A) 11
(B) 13
(C) 17
(D) 19
(E) 23

Try on your own
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Sexy triplets are in the form {p, (p + 6), (p + 12)}

Notice that the third term (p + 12) is 6 greater than the middle term (p + 6)
So, we can start by adding 6 to each answer choice to see whether the result (aka the third term) is prime.

(A) 11 + 6 = 17, and 17 IS prime.
(B) 13 + 6 = 19, and 19 IS prime.
(C) 17 + 6 = 23, and 23 IS prime.
(D) 19 + 6 = 25, and 25 is NOT prime.

Answer D
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A pair of prime numbers that can be expressed in the form {p 10 Jul 2014, 20:54
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Sitter.. Put in values and test.. Definitely not a 700 level question .If yes , then I am going great guns !! :D
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A pair of prime numbers that can be expressed in the form {p 11 Jul 2014, 12:02
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A pair of prime numbers that can be expressed in the form {p, (p + 6)} is defined as a pair of “sexy primes.” A “sexy triplet” is a group of three primes that can be expressed in the form {p, (p + 6), (p + 12)}. All of the following prime numbers are the middle term of a sexy triplet EXCEPT

(A) 11
(B) 13
(C) 17
(D) 19
(E) 23

Try on your own
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Agree. Does not seem to be a 700 question.

{x-6, x, x+6} all must be primes. Substitute options for x to check whether this will hold true. If x=19, then x+6=25, which is not a prime.

Answer: D.
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Bunuel

according to gmathacks is a 720 level. As such, two things we must to consider here: or jeff sackman is misleading in somehow or a real 700 level question is something quite similar to tensor analysis at this stage....

I have the GMAT question pack 1 and a 700 level question is not so far from the concept implied in this question or crafted I could say.

Waiting some thought by you.

thanks
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A pair of prime numbers that can be expressed in the form {p 12 Jul 2014, 14:14
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Bunuel

according to gmathacks is a 720 level. As such, two things we must to consider here: or jeff sackman is misleading in somehow or a real 700 level question is something quite similar to tensor analysis at this stage....

I have the GMAT question pack 1 and a 700 level question is not so far from the concept implied in this question or crafted I could say.

Waiting some thought by you.

thanks
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Don't think I can add much. I don't agree with gmathack on this question. You can easily solve it in 30 seconds. From my point of view, it's ~600 level.
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A pair of prime numbers that can be expressed in the form {p 12 Jul 2014, 14:30
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Thank you Sir.

Last thought in a more general way: from my experience what makes a 700 or more level question (truly gmat question) is not the calculation itself or some strange formula to apply but the wording of the same or something that is hidden in it.

I have solved questions in which the difficulty was really high and the video explanation was at least 4 minutes because of its complexity but on my own I solved it in 30 seconds thanks to my intuition to gather few information or solely based on observation of the same.

Anyhow, Thanks for clarification.
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A pair of prime numbers that can be expressed in the form {p 10 Apr 2016, 05:12
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definetly a sitter.plug in the values for middle term and calculate.We can see clearly that for 19 , 19+6 gives 25 which is not a prime
therefore correct answer D
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A pair of prime numbers that can be expressed in the form {p 10 Apr 2016, 22:05
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A sub-600 for me. Because, all you need to know to get this question is - "5, 17, 7, 19, 11, 23, 17 and 29 are primes and 25 is not." Moreover, the language in the question isn't too convoluted either. So, IMO, nothing makes it a 700-level.
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A pair of prime numbers that can be expressed in the form {p, (p + 6)} is defined as a pair of “sexy primes.” A “sexy triplet” is a group of three primes that can be expressed in the form {p, (p + 6), (p + 12)}. All of the following prime numbers are the middle term of a sexy triplet EXCEPT

(A) 11
(B) 13
(C) 17
(D) 19
(E) 23

Try on your own
Show more

If I'm understanding it correctly, the answer choices provided represent the "middle term of the sexy triplet".
(A) 5, 11, 23
(B) 7, 13, 25
(C) 11, 17, 29
(D) 13, 19, 31
(E) 17, 23, 35

I'm confused how it's D?
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A pair of prime numbers that can be expressed in the form {p 23 Sep 2021, 09:18
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A pair of prime numbers that can be expressed in the form {p, (p + 6)} is defined as a pair of “sexy primes.” A “sexy triplet” is a group of three primes that can be expressed in the form {p, (p + 6), (p + 12)}. All of the following prime numbers are the middle term of a sexy triplet EXCEPT

(A) 11
(B) 13
(C) 17
(D) 19
(E) 23

Try on your own

If I'm understanding it correctly, the answer choices provided represent the "middle term of the sexy triplet".
(A) 5, 11, 23
(B) 7, 13, 25
(C) 11, 17, 29
(D) 13, 19, 31
(E) 17, 23, 35

I'm confused how it's D?
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It's \(p + 12\). In option B you have computed \(13 + 12\) i.e. \(p + 6 + 12\) instead of \(7 + 12\) which is \(19\)

Run these corrections across other options and you will arrive at D

Hope it helps!
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