Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

11 May 2011, 18:17

00:00

A

B

C

D

E

Difficulty:

55% (hard)

Question Stats:

48% (01:13) correct 52% (01:52) wrong based on 33 sessions

HideShow timer Statistics

Set X consists of seven consecutive integers, and set Y consists of nine consecutive integers. Is the median of the numbers in set X equal to the median of the numbers in set Y ?

(1) The sum of the numbers in set X is equal to the sum of the numbers in set Y. (2) The median of the numbers in set Y is 0.

Re: Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

11 May 2011, 19:18

Evaluating 2) First. The mean of the set Y is known but the median of set X is unknown.

S2 also tells us that there are equal number of +ve and -ve numbers in set Y. But it is insufficient.

S1 Gives no information about the median of Y. Insufficient

1) + 2)

Sufficient. The only way to get the sum equal when X and Y have consecutive integers is to "symmetric" about the zero. Hence we are sure that median is zero for both sets. Sufficient

Re: Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

11 May 2011, 23:48

fanatico wrote:

Set X consists of seven consecutive integers, and set Y consists of nine consecutive integers. Is the median of the numbers in set X equal to the median of the numbers in set Y ? (1) The sum of the numbers in set X is equal to the sum of the numbers in set Y. (2) The median of the numbers in set Y is 0.

For set of consecutive integers Median=Mean. Mean of 7 consecutive integer = M7= Sum of 7 consecutive integers (S7) / 7 Mean of 9 consecutive integer = M9= Sum of 9 consecutive integers (S9) / 9 Question: M7=M9?

1) S7=S9. M7=S7/7 and M9=S9/9 IS M7=M9? Cannot say even if S7=S9. Take S7=S9=63. Different values of M7 and M9. Insufficient.

2) M9 = 0. We don't know M7. Insufficient.

Together, M9=0. Also, M9=S9/9. Hence S9=0. As S7=S9, S7=0. Hence M7=0/7 and M9=0/9. M7=M9. Sufficient.

OA C.
_________________

My dad once said to me: Son, nothing succeeds like success.

Re: Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

04 Dec 2011, 08:29

Set X consists of seven consecutive integers, and set Y consists of nine consecutive integers. Is the median of the numbers in set X equal to the median of the numbers in set Y ?

(1) The sum of the numbers in set X is equal to the sum of the numbers in set Y. (2) The median of the numbers in set Y is 0.

Re: Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

04 Dec 2011, 09:05

Statement 2: Does not talk about Set X: Not Sufficient Statement 1: I see only one possibility for set X and Y X= {-3,-2,-1,0,1,2,3} Y={-4,-3,-2,-1,0,1,2,3, 4} 0 being the median for both. Sufficient

Re: Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

04 Dec 2011, 10:07

dreambeliever wrote:

Set X consists of seven consecutive integers, and set Y consists of nine consecutive integers. Is the median of the numbers in set X equal to the median of the numbers in set Y ?

(1) The sum of the numbers in set X is equal to the sum of the numbers in set Y. (2) The median of the numbers in set Y is 0.

1- Insufficient

There are 7 consecutive integers in X. Lets say the smallest x. The others will be x+1...x+6 There are 9 consecutive integers in Y. Lets say the smallest y. The others will be y+1...y+8

Sum of X = 7x+21= 7.(x+3) Sum of Y = 9y+36 =9.(y+4)

if Sum of X = Sum of Y then makes 7(x+3)=9(y+4)..................(1) median of X = x+3 median of Y = y+4

if median of X = median of Y then 7(x+3) must be equal to 9 (x+3) it is possible in only one case that is x=-3.

So we do not infer from this statement that median of x is equal to median of y.

2) we do not know anything about X

getting them together we see that y+4= 0, so y = -4 and total of them are 0 and if total of X = 0 and X consists of 7 consequtive integers, X must be -3,..0,..3 So medians are equal

Re: Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

04 Dec 2011, 16:52

My answer is C. I was freaking out while scrolling down this thread....B, B and than OA was C..I was relieved.

Cheers!
_________________

----------------------------------------------------------------------------------------- What you do TODAY is important because you're exchanging a day of your life for it! -----------------------------------------------------------------------------------------

Re: Set X consists of seven consecutive integers, and set Y [#permalink]

Show Tags

04 Dec 2011, 23:31

Is using Algebra is the best way to deal with SET problem? i was using picking number and had tough to find sets for which the sum is equal (for this problem). Experts: any specific guidelines for this sort of set problem?

Set X consists of seven consecutive integers, and set Y consists of nine consecutive integers. Is the median of the numbers in set X equal to the median of the numbers in set Y ?

(1) The sum of the numbers in set X is equal to the sum of the numbers in set Y. (2) The median of the numbers in set Y is 0.

Set X consists of seven consecutive integers, and set Y consists of nine consecutive integers. Is the median of the numbers in set X equal to the median of the numbers in set Y?

Sets X and Y are evenly spaced. In any evenly spaced set (aka arithmetic progression): (mean) = (median) = (the average of the first and the last terms) and (the sum of the elements) = (the mean) * (# of elements).

So the question asks whether (mean of X) = (mean of Y)?

(1) The sum of the numbers in set X is equal to the sum of the numbers in set Y --> 7*(mean of X) = 9* (mean of Y) --> answer to the question will be YES in case (mean of X) = (mean of Y) = 0 and will be NO in all other cases (for example (mean of X) =9 and (mean of Y) = 7). Not sufficient. For example consider following two sets: Set X: {6, 7, 8, 9, 10, 11, 12} --> sum 63; Set Y: {3, 4, 5, 6, 7, 8, 9, 10, 11} --> sum 63.

(2) The median of the numbers in set Y is 0 --> (mean of Y) = 0, insufficient as we know nothing about the mean of X, which may or may not be zero.

(1)+(2) Since from (2) (mean of Y) = 0 and from (2) 7*(mean of X) = 9* (mean of Y) then (mean of X) = 0. Sufficient.