It is currently 20 Nov 2017, 01:19

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# The variable x takes on integer values between 1 and 7 inclusive as

Author Message
TAGS:

### Hide Tags

Director
Joined: 29 Nov 2012
Posts: 866

Kudos [?]: 1451 [1], given: 543

The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

08 Jan 2013, 21:25
1
KUDOS
10
This post was
BOOKMARKED
00:00

Difficulty:

25% (medium)

Question Stats:

72% (01:30) correct 28% (01:34) wrong based on 302 sessions

### HideShow timer Statistics

X frequency
1 3
2 1
3 3
4 1
5 3
6 1
7 3

The variable x takes on integer values between 1 and 7 inclusive as shown above. What is the probability that the absolute value of the difference between the mean of the distribution which is 4 and a randomly chosen value of x will be greater than 3/2?

A) 8/15
B) 4/7
C) 4/5
D) 6/7
E) 8/7

[Reveal] Spoiler:
Attachment:

DSCN0392.JPG [ 1002.27 KiB | Viewed 222 times ]
[Reveal] Spoiler: OA

_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios http://gmatclub.com/forum/gmat-prep-software-analysis-and-what-if-scenarios-146146.html

Last edited by fozzzy on 09 Jan 2013, 03:43, edited 1 time in total.

Kudos [?]: 1451 [1], given: 543

VP
Joined: 02 Jul 2012
Posts: 1216

Kudos [?]: 1691 [4], given: 116

Location: India
Concentration: Strategy
GMAT 1: 740 Q49 V42
GPA: 3.8
WE: Engineering (Energy and Utilities)
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

08 Jan 2013, 22:26
4
KUDOS
1
This post was
BOOKMARKED
The set is
1,1,1,2,3,3,3,4,5,5,5,6,7,7,7

The question basically asks for the probability of choosing 1,2,6 or 7.

= 8/15
_________________

Did you find this post helpful?... Please let me know through the Kudos button.

Thanks To The Almighty - My GMAT Debrief

GMAT Reading Comprehension: 7 Most Common Passage Types

Kudos [?]: 1691 [4], given: 116

Manager
Joined: 25 Jun 2012
Posts: 68

Kudos [?]: 134 [0], given: 21

Location: India
WE: General Management (Energy and Utilities)
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

08 Jan 2013, 22:47
MacFauz wrote:
The set is
1,1,1,2,3,3,3,4,5,5,5,6,7,7,7

The question basically asks for the probability of choosing 1,2,6 or 7.

= 8/15

Hi Can you please explain in detail?

how u got the values of set?

Kudos [?]: 134 [0], given: 21

VP
Joined: 02 Jul 2012
Posts: 1216

Kudos [?]: 1691 [6], given: 116

Location: India
Concentration: Strategy
GMAT 1: 740 Q49 V42
GPA: 3.8
WE: Engineering (Energy and Utilities)
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

08 Jan 2013, 22:58
6
KUDOS
bhavinshah5685 wrote:
MacFauz wrote:
The set is
1,1,1,2,3,3,3,4,5,5,5,6,7,7,7

The question basically asks for the probability of choosing 1,2,6 or 7.

= 8/15

Hi Can you please explain in detail?

how u got the values of set?

Looking at the table.,

The column on the left shows the value of X and the column on the right shows the number of times the value appears. The question statement is just beating around the bush a lot to ask a simple question. What is the probability that 4 - X > 1.5. For such a case, X has to be 1,2,6 or 7.
_________________

Did you find this post helpful?... Please let me know through the Kudos button.

Thanks To The Almighty - My GMAT Debrief

GMAT Reading Comprehension: 7 Most Common Passage Types

Kudos [?]: 1691 [6], given: 116

Manager
Joined: 04 Oct 2011
Posts: 216

Kudos [?]: 63 [1], given: 44

Location: India
GMAT 1: 440 Q33 V13
GPA: 3
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

09 Jan 2013, 20:47
1
KUDOS
MacFauz wrote:
bhavinshah5685 wrote:
MacFauz wrote:
The set is
1,1,1,2,3,3,3,4,5,5,5,6,7,7,7

The question basically asks for the probability of choosing 1,2,6 or 7.

= 8/15

Hi Can you please explain in detail?

how u got the values of set?

Looking at the table.,

The column on the left shows the value of X and the column on the right shows the number of times the value appears. The question statement is just beating around the bush a lot to ask a simple question. What is the probability that 4 - X > 1.5. For such a case, X has to be 1,2,6 or 7.

Hi MacFauz,
I guess answer is correct but the solution seems to be different to me. Pls correct me!

given absolute difference is
$$|4-X| >1.5$$
so
$$-1.5> |4-X| >1.5$$
solving this
$$2.5 < X < 6.5$$
This gives range from
3,3,3,4,5,5,5,6

Actually i did this wrong. On seeing ur solution i got it
_________________

GMAT - Practice, Patience, Persistence
Kudos if u like

Kudos [?]: 63 [1], given: 44

VP
Joined: 02 Jul 2012
Posts: 1216

Kudos [?]: 1691 [0], given: 116

Location: India
Concentration: Strategy
GMAT 1: 740 Q49 V42
GPA: 3.8
WE: Engineering (Energy and Utilities)
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

09 Jan 2013, 21:27
shanmugamgsn wrote:
MacFauz wrote:
bhavinshah5685 wrote:
The set is
1,1,1,2,3,3,3,4,5,5,5,6,7,7,7

The question basically asks for the probability of choosing 1,2,6 or 7.

= 8/15

Hi Can you please explain in detail?

how u got the values of set?

Looking at the table.,

The column on the left shows the value of X and the column on the right shows the number of times the value appears. The question statement is just beating around the bush a lot to ask a simple question. What is the probability that 4 - X > 1.5. For such a case, X has to be 1,2,6 or 7.

Hi MacFauz,
I guess answer is correct but the solution seems to be different to me. Pls correct me!

given absolute difference is
$$|4-X| >1.5$$
so
-1.5> |4-X| >1.5
solving this
$$2.5 < X < 6.5$$
This gives range from
3,3,3,4,5,5,5,6

Actually i did this wrong. On seeing ur solution i got it

The step in red is incorrect. You should note that the least value that |4-X| can take is 0. So, it can never be less than -1.5. The inequality should actually be X<2.5 or X>5.5.
_________________

Did you find this post helpful?... Please let me know through the Kudos button.

Thanks To The Almighty - My GMAT Debrief

GMAT Reading Comprehension: 7 Most Common Passage Types

Kudos [?]: 1691 [0], given: 116

Manager
Joined: 04 Oct 2011
Posts: 216

Kudos [?]: 63 [0], given: 44

Location: India
GMAT 1: 440 Q33 V13
GPA: 3
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

09 Jan 2013, 22:53
Actually it should be
-1.5> 4-X >1.5 (it was a typo above)

But still i didnt get u!
|4-X| can be zero ?
then |4-X|>1.5 will be 0>1.5

This isnt wrong?

Messed up
Pls explain
_________________

GMAT - Practice, Patience, Persistence
Kudos if u like

Kudos [?]: 63 [0], given: 44

VP
Joined: 02 Jul 2012
Posts: 1216

Kudos [?]: 1691 [0], given: 116

Location: India
Concentration: Strategy
GMAT 1: 740 Q49 V42
GPA: 3.8
WE: Engineering (Energy and Utilities)
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

09 Jan 2013, 22:58
shanmugamgsn wrote:
Actually it should be
-1.5> 4-X >1.5 (it was a typo above)

But still i didnt get u!
|4-X| can be zero ?
then |4-X|>1.5 will be 0>1.5

This isnt wrong?

Messed up
Pls explain

I guess I wasn't clear. What I meant to say was that a modulus value cannot be negative. Of course in this question, we want only values for which |4-X|>1.5. The range that you have given (-1.5> 4-X >1.5) is not a valid one. A number cannot be both greater than 1.5 and lesser than -1.5. Rather the interval should be 1.5 < 4-X OR 4-X < -1.5
_________________

Did you find this post helpful?... Please let me know through the Kudos button.

Thanks To The Almighty - My GMAT Debrief

GMAT Reading Comprehension: 7 Most Common Passage Types

Kudos [?]: 1691 [0], given: 116

Manager
Joined: 04 Oct 2011
Posts: 216

Kudos [?]: 63 [0], given: 44

Location: India
GMAT 1: 440 Q33 V13
GPA: 3
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

10 Jan 2013, 20:05
MacFauz wrote:
shanmugamgsn wrote:
Actually it should be
-1.5> 4-X >1.5 (it was a typo above)

But still i didnt get u!
|4-X| can be zero ?
then |4-X|>1.5 will be 0>1.5

This isnt wrong?

Messed up
Pls explain

I guess I wasn't clear. What I meant to say was that a modulus value cannot be negative. Of course in this question, we want only values for which |4-X|>1.5. The range that you have given (-1.5> 4-X >1.5) is not a valid one. A number cannot be both greater than 1.5 and lesser than -1.5. Rather the interval should be 1.5 < 4-X OR 4-X < -1.5

Thanks MacFauz...
ya i got my mistake in Inequalities.
Thanks dude...
_________________

GMAT - Practice, Patience, Persistence
Kudos if u like

Kudos [?]: 63 [0], given: 44

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1120

Kudos [?]: 2371 [1], given: 219

Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

29 Mar 2013, 00:51
1
KUDOS
x has values between 1 and 7 so $$|4-x|>\frac{3}{2}$$=

|4-1|=3>3/2
|4-2|=2>3/2
|4-3|=1>3/2
|4-4|=0>3/2
|4-5|=1>3/2

|4-6|=2>3/2
|4-7|=3>3/2

The value that respect |4-x|>3/2 are 1,2,6,7 that have a frequency of 3,1,1,3 so $$3+1+1+3$$ = total frequencies of "right" events, and this will be our numerator.
Our denominator will be the tot number of combinations = $$3+1+3+1+3+1+3= 15.$$
Answer $$\frac{8}{15}$$
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Kudos [?]: 2371 [1], given: 219

Intern
Joined: 18 Jul 2013
Posts: 1

Kudos [?]: [0], given: 0

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

18 Jul 2013, 03:44
I have a question regarding the denominator 15 : why do we take into consideration the value 4 since it occurs only once and we're looking for the the difference between this value and the others. I had the answer wrong because I assumed the denominator was 14 - could someone try to explain?

Kudos [?]: [0], given: 0

Director
Joined: 29 Nov 2012
Posts: 866

Kudos [?]: 1451 [0], given: 543

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

18 Jul 2013, 07:50
aa81 wrote:
I have a question regarding the denominator 15 : why do we take into consideration the value 4 since it occurs only once and we're looking for the the difference between this value and the others. I had the answer wrong because I assumed the denominator was 14 - could someone try to explain?

The question states

What is the probability that the absolute value of the difference between the mean of the distribution which is 4 and a randomly chosen value of x will be greater than 3/2?

you get 15 when you add the frequency ( 3+1+3 etc)

The set is

The set is
1,1,1,2,3,3,3,4,5,5,5,6,7,7,7

_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios http://gmatclub.com/forum/gmat-prep-software-analysis-and-what-if-scenarios-146146.html

Kudos [?]: 1451 [0], given: 543

Manager
Joined: 13 Dec 2012
Posts: 194

Kudos [?]: 110 [0], given: 29

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

18 Jul 2013, 08:41
fozzzy wrote:
X frequency
1 3
2 1
3 3
4 1
5 3
6 1
7 3

The variable x takes on integer values between 1 and 7 inclusive as shown above. What is the probability that the absolute value of the difference between the mean of the distribution which is 4 and a randomly chosen value of x will be greater than 3/2?

A) 8/15
B) 4/7
C) 4/5
D) 6/7
E) 8/7

How can the probability of doing something be 3/2?

How can the probability of doing something be greater than 1?

I don't understand what y'all are calculating.
_________________

Blog: The MBA Journey of an African Doctor

Blog updated: July 27, 2014

Kudos [?]: 110 [0], given: 29

Director
Joined: 29 Nov 2012
Posts: 866

Kudos [?]: 1451 [0], given: 543

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

18 Jul 2013, 09:29
knightofdelta wrote:

How can the probability of doing something be 3/2?

How can the probability of doing something be greater than 1?

I don't understand what y'all are calculating.

The final answer is below 1

8/15 = 0.5333
_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios http://gmatclub.com/forum/gmat-prep-software-analysis-and-what-if-scenarios-146146.html

Kudos [?]: 1451 [0], given: 543

Manager
Joined: 13 Dec 2012
Posts: 194

Kudos [?]: 110 [0], given: 29

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

18 Jul 2013, 09:35
fozzzy wrote:
knightofdelta wrote:

How can the probability of doing something be 3/2?

How can the probability of doing something be greater than 1?

I don't understand what y'all are calculating.

The final answer is below 1

8/15 = 0.5333

Then the answer should be 0 since the answer will be below 3/2. 3/2 is higher than 1 and the answer is below 1. Therefore, since the answer is certainly below 1 and 1 is below 3/2, then the answer is 0. And 0 is not one of the answer choices.

Summary: the question is faulty.
_________________

Blog: The MBA Journey of an African Doctor

Blog updated: July 27, 2014

Kudos [?]: 110 [0], given: 29

Math Expert
Joined: 02 Sep 2009
Posts: 42262

Kudos [?]: 132745 [0], given: 12371

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

21 Jul 2013, 02:41
knightofdelta wrote:
fozzzy wrote:
knightofdelta wrote:

How can the probability of doing something be 3/2?

How can the probability of doing something be greater than 1?

I don't understand what y'all are calculating.

The final answer is below 1

8/15 = 0.5333

Then the answer should be 0 since the answer will be below 3/2. 3/2 is higher than 1 and the answer is below 1. Therefore, since the answer is certainly below 1 and 1 is below 3/2, then the answer is 0. And 0 is not one of the answer choices.

Summary: the question is faulty.

Please read the question carefully. The question asks "what is the probability that SOME VALUE will be greater than 3/2?" not "is the probability of SOME EVENT greater than 3/2?"
_________________

Kudos [?]: 132745 [0], given: 12371

Intern
Joined: 01 Apr 2014
Posts: 1

Kudos [?]: [0], given: 0

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

03 Sep 2015, 18:21
Hi,

Can someone explain why we have considered frequencies while the stem asks us about the value of X?

I mean, the probability of abs (4-X) >1.5 , then what values of X can be considered ?

Or did i miss something?

Kudos [?]: [0], given: 0

Non-Human User
Joined: 09 Sep 2013
Posts: 15639

Kudos [?]: 283 [0], given: 0

Re: The variable x takes on integer values between 1 and 7 inclusive as [#permalink]

### Show Tags

02 Nov 2017, 08:54
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

Kudos [?]: 283 [0], given: 0

Re: The variable x takes on integer values between 1 and 7 inclusive as   [#permalink] 02 Nov 2017, 08:54
Display posts from previous: Sort by