GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 20 Oct 2019, 04:21

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.

Close

Request Expert Reply

Confirm Cancel

x is an integer greater than 7. What is the median of the set of integ

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 58434
x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 14 Oct 2014, 06:20
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

54% (01:43) correct 46% (01:56) wrong based on 215 sessions

HideShow timer Statistics

Current Student
User avatar
P
Status: Chasing my MBB Dream!
Joined: 29 Aug 2012
Posts: 1100
Location: United States (DC)
WE: General Management (Aerospace and Defense)
GMAT ToolKit User Reviews Badge
x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 14 Oct 2014, 08:00
1
2
Bunuel wrote:

Tough and Tricky questions: Statistics.



x is an integer greater than 7. What is the median of the set of integers from 1 to x inclusive?

(1) The average of the set of integers from 1 to x inclusive is 11.
(2) The range of the set of integers from 1 to x inclusive is 20.



X>7 and the set (let it be S) contains 1 to X inclusive.

I normally read both the statements and start with the easier one. In this case, it is statement 2.

Statement 2: If the range is 20. Then X must be 21. Since X is the last term. In this case, we can easily find the median. So Sufficient.

Statement 1: If we know the average of the set, we can find the sum and number of elements in the set. But this is a tedious process to jot down all the numbers and find the sum.

But we can use statement 2 as a clue to solve this easily without crushing our brain. Since two statements never contradicts each other. If we plugin X as 21. We get the sum as 231(using the sum of n numbers formula) and average as 11.

Bingo!!

We can find the median from this statement as well. So Sufficient.

Answer : D: Both statement Individually sufficient to solve.
_________________
Senior Manager
Senior Manager
User avatar
Joined: 13 Jun 2013
Posts: 266
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 14 Oct 2014, 08:43
1
1
Gnpth wrote:
Bunuel wrote:

Tough and Tricky questions: Statistics.



x is an integer greater than 7. What is the median of the set of integers from 1 to x inclusive?

(1) The average of the set of integers from 1 to x inclusive is 11.
(2) The range of the set of integers from 1 to x inclusive is 20.



X>7 and the set (let it be S) contains 1 to X inclusive.

I normally read both the statements and start with the easier one. In this case, it is statement 2.

Statement 2: If the range is 20. Then X must be 21. Since X is the last term. In this case, we can easily find the median. So Sufficient.

Statement 1: If we know the average of the set, we can find the sum and number of elements in the set. But this is a tedious process to jot down all the numbers and find the sum.

But we can use statement 2 as a clue to solve this easily without crushing our brain. Since two statements never contradicts each other. If we plugin X as 21. We get the sum as 231(using the sum of n numbers formula) and average as 11.

Bingo!!

We can find the median from this statement as well. So Sufficient.

Answer : D: Both statement Individually sufficient to solve.


we can solve statement 1 in the following manner

since number are consecutive integers. therefore there sum from 1 to x can be given as (x(1+x))/2; where x is the last term

now average is =11
thus (x(1+x))/2) =11x
1+x=22
or x=21
Intern
Intern
User avatar
Joined: 20 Apr 2012
Posts: 3
Location: Thailand
Concentration: Finance
GMAT 1: 570 Q38 V31
GMAT 2: 540 Q43 V21
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 16 Oct 2014, 01:18
Sorry to ask stupid question,

I answered E because the question is not explicitly telling that this set is consecutive. So, I assume it's not. But how do you know that it is??
_________________
People don't FAIL, they just stop TRYING....
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 58434
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 16 Oct 2014, 07:44
Manager
Manager
User avatar
S
Joined: 22 Jan 2014
Posts: 170
WE: Project Management (Computer Hardware)
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 02 Nov 2014, 02:45
Bunuel wrote:

Tough and Tricky questions: Statistics.



x is an integer greater than 7. What is the median of the set of integers from 1 to x inclusive?

(1) The average of the set of integers from 1 to x inclusive is 11.
(2) The range of the set of integers from 1 to x inclusive is 20.


D.

1) Avg = 11
sum of consecutive integers from 1 to x (inclusive) = x(x+1)/2
avg = {x(x+1)/2*x} = 11
or x = 21
so median can be calculated. sufficient.

2) range = 20
x = 21
again media can be calculated. sufficient.
_________________
Illegitimi non carborundum.
Senior Manager
Senior Manager
User avatar
G
Joined: 19 Oct 2012
Posts: 258
Location: India
Concentration: General Management, Operations
GMAT 1: 660 Q47 V35
GMAT 2: 710 Q50 V38
GPA: 3.81
WE: Information Technology (Computer Software)
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 04 Mar 2016, 09:52
For an evenly spaced out set, the mean == median.
here the set is space of consecutive integers.
Stmt1: Sufficient.
Stmt2: x-1= 20; x=21. Avg==mean =11. Sufficient.
Therefore D.
_________________
Citius, Altius, Fortius
Intern
Intern
User avatar
Joined: 23 Dec 2015
Posts: 21
x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 04 Mar 2016, 18:40
Statement 1: AM(average ) of an arithmetic progression = (a+L) /2
a ------> first term of the series
L ------> last term of the series
This gives 11= (1+x)/2 ( since 1 is the first term and x is the last term of the series)
therefore x= 21
so sufficient to find the median

Statement 2: range is 20 therfore x=21
Sufficient

Answer: D
Intern
Intern
avatar
Joined: 20 Dec 2018
Posts: 46
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 21 Dec 2018, 22:27
)Statement 1. If a set has equally distant elements i.e. if the set is in A.P., then the mean of the set is also the median of the set.
Here, we are given the mean of the set and we are told that the set is in A.P. So, the median would also be 11. Hence, Sufficient.
Statement 2. Range of a set = (Biggest element – smallest element)
We know that the smallest no is 1 and the range of the set is 20. So, the biggest number should be 21.
Now, We can easily find the median of the set consisting of integers from 1 to 21.
The median is 11. Hence, Sufficient.
Intern
Intern
avatar
Joined: 20 Dec 2018
Posts: 46
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 21 Dec 2018, 22:29
Probability of picking 1 vowel from Set#1 = 2/5
Probability of not picking any vowel from Set#1 = 3/5
Probability of picking 1 vowel from Set#2 = 1/6
Probability of not picking any vowel from Set#2 = 5/6
Probability of picking atleast 1 vowel= P(2 vowels) + P(vowel from Set#1 & consonant from Set#2) + P(vowel from Set#2 & consonant from Set#1)
Probability of picking atleast 1 vowel = 2/5 x 1/6 + 2/5 x 5/6 + 3/5 x 1/6 = 15/30 = 1/2.
Intern
Intern
avatar
Joined: 03 Jan 2019
Posts: 1
Re: x is an integer greater than 7. What is the median of the set of integ  [#permalink]

Show Tags

New post 22 Jan 2019, 20:24
Bunuel wrote:
Phunnie wrote:
Sorry to ask stupid question,

I answered E because the question is not explicitly telling that this set is consecutive. So, I assume it's not. But how do you know that it is??


We are told that the set consists of integers from 1 to x inclusive, so the set consists of consecutive integers. For example, if x=8, then set is {1, 2, 3, 4, 5, 6, 7, 8}.




Can we always consider "the set consists of integers from 1 to x inclusive" as "a set of consecutive integers"? I really got stuck here. I thought the integers are not evenly spaced and can be repeated.

Can you suggest any material talk about this idea? Thank you.
GMAT Club Bot
Re: x is an integer greater than 7. What is the median of the set of integ   [#permalink] 22 Jan 2019, 20:24
Display posts from previous: Sort by

x is an integer greater than 7. What is the median of the set of integ

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne