OG2015 DS n, 15, 12, 9,

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OG2015 DS n, 15, 12, 9,

by lionsshare » Sat Sep 16, 2017 2:24 am
n, 15, 12, 9, 20
What is the value of n in the list above?

(1) n> 12
(2) The median of the numbers in the list is 13.

OA: B

The statements are quite ambiguous to me. Anyone, please explain the solution to this problem. Thanks a bunch!

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by Jay@ManhattanReview » Sat Sep 16, 2017 4:52 am
lionsshare wrote:n, 15, 12, 9, 20
What is the value of n in the list above?

(1) n> 12
(2) The median of the numbers in the list is 13.

OA: B

The statements are quite ambiguous to me. Anyone, please explain the solution to this problem. Thanks a bunch!
Statement 1: n > 12

Certainly not helpful. n can have any value under the Sun. Insufficient.

Statement 2: The median of the numbers in the list is 13.

Since the statement refers to the median, we must first arrange the given list in an ascending order.

The arranged list in the ascending order: 9, 12, 15, 20; let's leave n for the time being.

Since there are five numbers in the set, the median would be the middle-most number, i.e., the third number. We know that median = 13, which is not among the given four numbers, n must be 13. Sufficient.

The correct answer: B

Hope this helps!

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by Scott@TargetTestPrep » Sun Jul 22, 2018 5:20 pm
lionsshare wrote:n, 15, 12, 9, 20
What is the value of n in the list above?

(1) n> 12
(2) The median of the numbers in the list is 13.
We need to determine the value of n in the list: n, 15, 12, 9, 20.

Statement One Alone:

n > 12

Only knowing that n > 12 is not enough to determine the value of n. For example, n can be 13 or 14 (or some other number greater than 12). Statement one alone does not provide enough information to answer the question.

Statement Two Alone:

The median of the numbers in the list is 13.

We are given a list of 5 values: n, 15, 12, 9, and 20. Since we have 5 numbers in the list (an odd number of values), the median is equal to the middle value when the data are ordered from least to greatest. Using statement two, when the values are ordered from least to greatest, the list looks like the following:

9, 12, 13, 15, 20

Since 13 is not one of the four known values in the list, we see that 13 must be equal to n.

Answer: B

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by [email protected] » Fri Jul 27, 2018 10:42 am
Hi All,

We're given a list of 5 values: N, 15, 12, 9, and 20. We're asked for the value of N.

1) N > 12

With the information in Fact 1, we know that N could be ANY value greater than 12, but that gives us an infinite number of possible values for N.
Fact 1 is INSUFFICIENT

2) The median of the numbers in the list is 13.

The word "median" means "middle number." To find the median in a group of 5 terms, we have to first put the numbers in order from least to greatest. With the information in Fact 2, we KNOW that the median = 13 - and since none of the 4 numbers (in the group of 5 values) is 13, the missing term (re: N) MUST be 13...
9, 12, 13, 15, 20
Fact 2 is SUFFICIENT

Final Answer: B

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