Last visit was: 19 May 2026, 03:37 It is currently 19 May 2026, 03:37
Home
Messages
Tests
Schools
Events
Close
GMAT Club Daily Prep
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
User avatar
bmwhype2
User avatar
Joined: 21 Jan 2007
Last visit: 08 Mar 2010
Posts: 1,333
Own Kudos:
5,570
Given Kudos: 4
Location: New York City
Posts: 1,333
Kudos: 5,570
Given Set X = ( 3, 5, 9, 13, y ) what is y if the median and 18 May 2007, 16:30
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Given
Set X = ( 3, 5, 9, 13, y )

what is y if the median and mean are equal?

=3+5+9+13+y
=30+y

30 + y = 5N

i'm stuck...



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
User avatar
Himalayan
User avatar
Joined: 26 Feb 2006
Last visit: 09 Aug 2011
Posts: 383
Own Kudos:
634
Posts: 383
Kudos: 634
Given Set X = ( 3, 5, 9, 13, y ) what is y if the median and 18 May 2007, 19:59
Kudos
Add Kudos
Bookmarks
Bookmark this Post
bmwhype2
Given
Set X = ( 3, 5, 9, 13, y )

what is y if the median and mean are equal?

=3+5+9+13+y
=30+y

30 + y = 5N

i'm stuck...
Show more


mean = (3+5+9+13+y)/5 = (30+y)/5 = 6 + y/5
Median = (5+1)/2 = 3rd number in acending order.

the choices for median are 5, 9 and y. y could be median if it is positive and is in between 5 and 9. lets try:

suppose mean = median = 5. if so y is -5.
suppose mean = median = 9. if so y is 15.
suppose mean = median = y. if so y is 7.5

all values are possible here.

seems the question is not complete because it should be giving us one one answer not multiple.
User avatar
bmwhype2
User avatar
Joined: 21 Jan 2007
Last visit: 08 Mar 2010
Posts: 1,333
Own Kudos:
5,570
Given Kudos: 4
Location: New York City
Posts: 1,333
Kudos: 5,570
Given Set X = ( 3, 5, 9, 13, y ) what is y if the median and 18 May 2007, 21:24
Kudos
Add Kudos
Bookmarks
Bookmark this Post
the exact question

(3, 5, 9, 13, y)

if the average (arithemetic mean) of the set of numbers above is equal to the median of the same set of number above, then what is the value of y?

a 7
b 8
c 10
d 15
e 17
User avatar
Himalayan
User avatar
Joined: 26 Feb 2006
Last visit: 09 Aug 2011
Posts: 383
Own Kudos:
634
Posts: 383
Kudos: 634
Given Set X = ( 3, 5, 9, 13, y ) what is y if the median and 18 May 2007, 21:25
Kudos
Add Kudos
Bookmarks
Bookmark this Post
bmwhype2
the exact question

(3, 5, 9, 13, y)

if the average (arithemetic mean) of the set of numbers above is equal to the median of the same set of number above, then what is the value of y?

a 7
b 8
c 10
d 15
e 17
Show more


from my calculation above, y = 15
User avatar
gmatiscoming
User avatar
Joined: 04 May 2007
Last visit: 28 Aug 2007
Posts: 71
Own Kudos:
27
Posts: 71
Kudos: 27
Given Set X = ( 3, 5, 9, 13, y ) what is y if the median and 21 May 2007, 21:41
Kudos
Add Kudos
Bookmarks
Bookmark this Post
the are giving you the median as 9 and telling you the mean will also equal n9. i guess this one is tricky, since sets don't have to be in order - although you have to put them in order to find the median, they aren't flat out telling you that the set is in ascending order.

but the calculation is

(3+5+9+13+y)/5 =9
30+y = 45
y =15
User avatar
saurster
User avatar
Joined: 18 Sep 2006
Last visit: 14 Apr 2008
Posts: 22
Own Kudos:
4
Posts: 22
Kudos: 4
Given Set X = ( 3, 5, 9, 13, y ) what is y if the median and 22 May 2007, 22:10
Kudos
Add Kudos
Bookmarks
Bookmark this Post
gmatiscoming; it appears that the set is ordered (ascending) so they don't need to tell you. However, its always better to check anyways...good job
User avatar
Bluebird
User avatar
Joined: 18 Apr 2007
Last visit: 08 Feb 2008
Posts: 56
Own Kudos:
7
Posts: 56
Kudos: 7
Given Set X = ( 3, 5, 9, 13, y ) what is y if the median and 23 May 2007, 13:27
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I agree with the answer of 15.

Assuming that the set is not ordered, we know that the mean = (30+y)/5

In order for the mean to be 3, (30+y) would have to equal 15, therefore, y would equal -15. Not a choice.

In order for the mean to equal 5, (30+y) would have to equal 25, therefore y = -5. Again, not a choice.

In order for the mean to equal 9, (30+y) would have to equal 45, therefore, y=15. This is a choice. A quick glance shows that y=15 also satisfies 9 as the median.

Answer: y=15



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!