Last visit was: 25 Apr 2024, 02:17 It is currently 25 Apr 2024, 02:17

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
SORT BY:
Date
User avatar
Manager
Manager
Joined: 05 Mar 2011
Status:Retaking next month
Affiliations: None
Posts: 105
Own Kudos [?]: 752 [263]
Given Kudos: 42
Location: India
Concentration: Marketing, Entrepreneurship
GMAT 1: 570 Q42 V27
GPA: 3.01
WE:Sales (Manufacturing)
Send PM
Most Helpful Reply
Tutor
Joined: 16 Oct 2010
Posts: 14822
Own Kudos [?]: 64907 [63]
Given Kudos: 426
Location: Pune, India
Send PM
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618882 [46]
Given Kudos: 81595
Send PM
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618882 [39]
Given Kudos: 81595
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
25
Kudos
14
Bookmarks
Expert Reply
fameatop wrote:
Hey bunuel,
I am able to get the analogy but I still can't apply that analogy to this case. Kindly explain once more
You said "The main point is that the minimum possible range of the three test-takers can no way be less than the largest range of the three test-takers, which is 35."
If the one of the possible distribution of marks is mentioned below - then the minimum possible range in scores of the three test-takers should be 7-0 = 7.
17 17 17 17 34
7 7 7 7 35
0 0 0 0 35

Thanks in advance


Your example:
{17, 17, 17, 17, 34} --> range=17;
{7, 7, 7, 7, 35} --> range=28;
{0, 0, 0, 0, 35} --> range=35.

All 15 scores: {0, 0, 0, 0, 7, 7, 7, 7, 17, 17, 17, 17, 34, 35, 35} --> range=35-0=35, not 7.

Hope it's clear.
Tutor
Joined: 16 Oct 2010
Posts: 14822
Own Kudos [?]: 64907 [33]
Given Kudos: 426
Location: Pune, India
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
19
Kudos
14
Bookmarks
Expert Reply
shankar245 wrote:
Hi Bunuel/Karihsma,


Can you please may be explain in a bit more detail the minimum part.
I'm stuck with question of possibilities, I mean what if the first set had this value or that value.

thanks


The minimum range of the entire group will be the maximum range of individuals.
Say there are 3 people:
Anna - 30, 38, 45, 46, 47 - Range 17
Beth - 20, 29, 36, 39, 48 - Range 28
Candi - 20, 25, 39, 49, 55 - Range 35

So Candi has 2 scores such that they have a difference of 35 between them (the smallest and the greatest scores).
When we put everyone's scores together and try to find the range, these two scores will still be there. There is a difference of 35 between them and that will stay. So no matter what, the range will be at least 35. In this case the lowest score out of all is 20 and highest is 55 so the range will be 35.

It could be more as well. E.g.

Anna - 30, 38, 45, 46, 47 - Range 17
Beth - 10, 19, 26, 29, 38 - Range 28
Candi - 20, 25, 39, 49, 55 - Range 35

Now taking all scores together, lowest score is 10 and highest is 55 so range becomes 45.

It can keep increasing in this way.
General Discussion
User avatar
Manager
Manager
Joined: 10 Jan 2010
Posts: 112
Own Kudos [?]: 56 [1]
Given Kudos: 7
Location: Germany
Concentration: Strategy, General Management
Schools: IE '15 (M)
GPA: 3
WE:Consulting (Telecommunications)
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
1
Kudos
Just to clarify the approach here.

It may look like this and would be correct, or?

17 17 17 17 34
7 7 7 7 35
0 0 0 0 35

Would be the same minimum range?!?
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618882 [8]
Given Kudos: 81595
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
1
Kudos
7
Bookmarks
Expert Reply
MSoS wrote:
Just to clarify the approach here.

It may look like this and would be correct, or?

17 17 17 17 34
7 7 7 7 35
0 0 0 0 35

Would be the same minimum range?!?


Yes. The main point is that the minimum possible range of the three test-takers can no way be less than the largest range of the three test-takers, which is 35.
Senior Manager
Senior Manager
Joined: 24 Aug 2009
Posts: 388
Own Kudos [?]: 2260 [0]
Given Kudos: 276
Concentration: Finance
Schools:Harvard, Columbia, Stern, Booth, LSB,
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
Hey bunuel,
I am able to get the analogy but I still can't apply that analogy to this case. Kindly explain once more
You said "The main point is that the minimum possible range of the three test-takers can no way be less than the largest range of the three test-takers, which is 35."
If the one of the possible distribution of marks is mentioned below - then the minimum possible range in scores of the three test-takers should be 7-0 = 7.
17 17 17 17 34
7 7 7 7 35
0 0 0 0 35

Thanks in advance
Senior Manager
Senior Manager
Joined: 17 Mar 2010
Status:Final Countdown
Posts: 320
Own Kudos [?]: 1305 [6]
Given Kudos: 76
Location: United States (NY)
GPA: 3.82
WE:Account Management (Retail Banking)
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
5
Kudos
1
Bookmarks
Three people each took 5 tests. If the ranges of their scores in the 5 practice tests were 17, 28 and 35, what is the minimum possible range in scores of the three test-takers?

A. 17
B. 28
C. 35
D. 45
E. 80

Min possible range. That means the lowest possible difference in total 15 values.

0 0 0 0 17
0 0 0 0 28
0 0 0 0 35

Minimum possible range is 35.


Range = Max-Min
=35-0
=35 ?


Am i right?
User avatar
Manager
Manager
Joined: 12 Jan 2013
Posts: 54
Own Kudos [?]: 134 [7]
Given Kudos: 13
Location: United States (NY)
GMAT 1: 780 Q51 V47
GPA: 3.89
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
7
Kudos
This problem took me 27 seconds, according to the timer. I took note of my own thinking while I was solving this problem.

I visualized three intervals of length 17, 28, and 35, respectively. Then I felt, intuitively, that the intervals were independent, so I visualized the smaller intervals as covered by the larger one. So I felt that the answer should be the greatest of the numbers. I looked at the numbers again and chose 35. Then I spent a few seconds making sure that I was answering the right question since it seemed too easy.

On an actual exam I would've double-checked myself by coming up with an actual example of fifteen scores, as explained above - provided, of course, that I had enough time.
User avatar
Manager
Manager
Joined: 13 Jun 2011
Status:Do till 740 :)
Posts: 61
Own Kudos [?]: 31 [0]
Given Kudos: 19
Concentration: Strategy, General Management
GMAT 1: 460 Q35 V20
GPA: 3.6
WE:Consulting (Computer Software)
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
Hi Bunuel/Karihsma,


Can you please may be explain in a bit more detail the minimum part.
I'm stuck with question of possibilities, I mean what if the first set had this value or that value.

thanks
User avatar
Intern
Intern
Joined: 08 Sep 2010
Posts: 44
Own Kudos [?]: 75 [0]
Given Kudos: 22
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
Bunuel wrote:
GMATPASSION wrote:
Three people each took 5 tests. If the ranges of their scores in the 5 practice tests were 17, 28 and 35, what is the minimum possible range in scores of the three test-takers?

A. 17
B. 28
C. 35
D. 45
E. 80

Min possible range. That means the lowest possible difference in total 15 values.

0 0 0 0 17
0 0 0 0 28
0 0 0 0 35

Minimum possible range is 35. Oh got the trick.

But my question is If I am thrown a question like this in the test I might panic & try many different kind of values. Is there a particular strategy or pattern for this type of questions.


Try to look at it as overlapping sets problem:
# of people in group A is 17;
# of people in group B is 28;
# of people in group C is 35;

What is the minimum # of total people possible in all 3 groups? Clearly if two smaller groups A and B are subsets of bigger group C (so if all people who are in A are also in C and all people who are in B are also in C), then total # of people in all 3 groups will be 35. Minimum # of total people can not possibly be less than 35 since there are already 35 people in group C.

Answer: C.

Hope it's clear.

P.S. Notice that max range for the original question is not limited when the max # of people in all 3 groups for revised question is 17+28+35 (in case there is 0 overlap between the 3 groups).



Hi Bunuel - Great explanation. Do we have similar kind of questions for practice?
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618882 [2]
Given Kudos: 81595
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
2
Bookmarks
Expert Reply
chanakya84 wrote:
Bunuel wrote:
GMATPASSION wrote:
Three people each took 5 tests. If the ranges of their scores in the 5 practice tests were 17, 28 and 35, what is the minimum possible range in scores of the three test-takers?

A. 17
B. 28
C. 35
D. 45
E. 80

Min possible range. That means the lowest possible difference in total 15 values.

0 0 0 0 17
0 0 0 0 28
0 0 0 0 35

Minimum possible range is 35. Oh got the trick.

But my question is If I am thrown a question like this in the test I might panic & try many different kind of values. Is there a particular strategy or pattern for this type of questions.


Try to look at it as overlapping sets problem:
# of people in group A is 17;
# of people in group B is 28;
# of people in group C is 35;

What is the minimum # of total people possible in all 3 groups? Clearly if two smaller groups A and B are subsets of bigger group C (so if all people who are in A are also in C and all people who are in B are also in C), then total # of people in all 3 groups will be 35. Minimum # of total people can not possibly be less than 35 since there are already 35 people in group C.

Answer: C.

Hope it's clear.

P.S. Notice that max range for the original question is not limited when the max # of people in all 3 groups for revised question is 17+28+35 (in case there is 0 overlap between the 3 groups).



Hi Bunuel - Great explanation. Do we have similar kind of questions for practice?


Yes, check all min/max questions here: search.php?search_id=tag&tag_id=63

Hope it helps.
Intern
Intern
Joined: 07 May 2017
Posts: 5
Own Kudos [?]: 1 [0]
Given Kudos: 10
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
VeritasPrepKarishma wrote:
shankar245 wrote:
Hi Bunuel/Karihsma,


Can you please may be explain in a bit more detail the minimum part.
I'm stuck with question of possibilities, I mean what if the first set had this value or that value.

thanks


The minimum range of the entire group will be the maximum range of individuals.
Say there are 3 people:
Anna - 30, 38, 45, 46, 47 - Range 17
Beth - 20, 29, 36, 39, 48 - Range 28
Candi - 20, 25, 39, 49, 55 - Range 35

So Candi has 2 scores such that they have a difference of 35 between them (the smallest and the greatest scores).
When we put everyone's scores together and try to find the range, these two scores will still be there. There is a difference of 35 between them and that will stay. So no matter what, the range will be at least 35. In this case the lowest score out of all is 20 and highest is 55 so the range will be 35.

It could be more as well. E.g.

Anna - 30, 38, 45, 46, 47 - Range 17
Beth - 10, 19, 26, 29, 38 - Range 28
Candi - 20, 25, 39, 49, 55 - Range 35

Now taking all scores together, lowest score is 10 and highest is 55 so range becomes 45.

It can keep increasing in this way.


I'm trying to understand this question and the closest I can get to understanding is your answer. However, the original question does not tell us what their individual scores were. It only gives us ranges. Is your explanation still valid if their scores were:

Anna: 6, 12, 14, 16, 23 - range 17
Beth: 8, 10, 12, 14, 36 - range 28
Candi: 10, 12, 14, 20, 45 - range 35

Wouldn't now the minimum range be from 6-45, which is 39? The question tells us the ranges, it seems to me that everyone just assumes that Anna's lowest score was higher than Beth's and Candi's lowest score and that Anna's highest score is also lower than Beth's and Candi's (so that her scores fall right in the middle of the other two's scores and so on).

Thank you!
Tutor
Joined: 16 Oct 2010
Posts: 14822
Own Kudos [?]: 64907 [2]
Given Kudos: 426
Location: Pune, India
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
2
Kudos
Expert Reply
wodan wrote:
VeritasPrepKarishma wrote:
shankar245 wrote:
Hi Bunuel/Karihsma,


Can you please may be explain in a bit more detail the minimum part.
I'm stuck with question of possibilities, I mean what if the first set had this value or that value.

thanks


The minimum range of the entire group will be the maximum range of individuals.
Say there are 3 people:
Anna - 30, 38, 45, 46, 47 - Range 17
Beth - 20, 29, 36, 39, 48 - Range 28
Candi - 20, 25, 39, 49, 55 - Range 35

So Candi has 2 scores such that they have a difference of 35 between them (the smallest and the greatest scores).
When we put everyone's scores together and try to find the range, these two scores will still be there. There is a difference of 35 between them and that will stay. So no matter what, the range will be at least 35. In this case the lowest score out of all is 20 and highest is 55 so the range will be 35.

It could be more as well. E.g.

Anna - 30, 38, 45, 46, 47 - Range 17
Beth - 10, 19, 26, 29, 38 - Range 28
Candi - 20, 25, 39, 49, 55 - Range 35

Now taking all scores together, lowest score is 10 and highest is 55 so range becomes 45.

It can keep increasing in this way.


I'm trying to understand this question and the closest I can get to understanding is your answer. However, the original question does not tell us what their individual scores were. It only gives us ranges. Is your explanation still valid if their scores were:

Anna: 6, 12, 14, 16, 23 - range 17
Beth: 8, 10, 12, 14, 36 - range 28
Candi: 10, 12, 14, 20, 45 - range 35

Wouldn't now the minimum range be from 6-45, which is 39? The question tells us the ranges, it seems to me that everyone just assumes that Anna's lowest score was higher than Beth's and Candi's lowest score and that Anna's highest score is also lower than Beth's and Candi's (so that her scores fall right in the middle of the other two's scores and so on).

Thank you!


Yes, you are right that in this case the range will be 39. But note that we are looking for the minimum possible range. Is it possible to reduce the range? Yes. Try to make it as small as possible. Make Anna's and Beth's lowest scores higher than Candi's lowest score and make their highest scores lower than Candi's highest score. That ways, you can reduce the range of all scores to Candi's range.
Manager
Manager
Joined: 08 Jun 2017
Posts: 50
Own Kudos [?]: 3 [0]
Given Kudos: 24
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
Is the question worded properly?I am not able to understand it
Tutor
Joined: 16 Oct 2010
Posts: 14822
Own Kudos [?]: 64907 [1]
Given Kudos: 426
Location: Pune, India
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
1
Kudos
Expert Reply
Anazeer wrote:
Is the question worded properly?I am not able to understand it


Yes, the wording is fine. "range" for 5 test scores would be (Max score - Min score).

Three people each took 5 tests. If the ranges of their scores in the 5 practice tests were 17, 28 and 35, what is the minimum possible range in scores of the three test-takers?

Range for person 1 was 17. So he tool 5 tests and got 5 scores. If Max is his maximum score of the 5 and Min is his minimum score of the 5, Max - Min = 17.
Similarly, for the other two, Max - Min is 28 and 35 respectively.

So now we need the minimum possible range of all scores of all three test takers. So we have 15 test scores and we need the minimum value possible for their range.

Does this help?

I have given the solution here: https://gmatclub.com/forum/three-people ... l#p1212587
Intern
Intern
Joined: 01 Dec 2017
Posts: 10
Own Kudos [?]: 3 [0]
Given Kudos: 15
Location: Italy
Schools: IMD Jan'18
GMAT 1: 680 Q46 V38
GPA: 4
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
Bunuel wrote:
GMATPASSION wrote:
Three people each took 5 tests. If the ranges of their scores in the 5 practice tests were 17, 28 and 35, what is the minimum possible range in scores of the three test-takers?

A. 17
B. 28
C. 35
D. 45
E. 80

Min possible range. That means the lowest possible difference in total 15 values.

0 0 0 0 17
0 0 0 0 28
0 0 0 0 35

Minimum possible range is 35. Oh got the trick.

But my question is If I am thrown a question like this in the test I might panic & try many different kind of values. Is there a particular strategy or pattern for this type of questions.


Try to look at it as overlapping sets problem:
# of people in group A is 17;
# of people in group B is 28;
# of people in group C is 35;

What is the minimum # of total people possible in all 3 groups? Clearly if two smaller groups A and B are subsets of bigger group C (so if all people who are in A are also in C and all people who are in B are also in C), then total # of people in all 3 groups will be 35. Minimum # of total people can not possibly be less than 35 since there are already 35 people in group C.

Answer: C.

Hope it's clear.

P.S. Notice that max range for the original question is not limited when the max # of people in all 3 groups for revised question is 17+28+35 (in case there is 0 overlap between the 3 groups).


Sorry Bunuel but I am still not convinced by this explanation..... for example if you have the following votes:

1 1 1 1 18
1 1 1 1 29
4 4 4 4 39

You would have range 35 for third group, but the range of all three groups would be 39-1= 38 > 35 ?
what am I missing?
Thanks
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618882 [0]
Given Kudos: 81595
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
Expert Reply
teone83 wrote:
Bunuel wrote:
GMATPASSION wrote:
Three people each took 5 tests. If the ranges of their scores in the 5 practice tests were 17, 28 and 35, what is the minimum possible range in scores of the three test-takers?

A. 17
B. 28
C. 35
D. 45
E. 80

Min possible range. That means the lowest possible difference in total 15 values.

0 0 0 0 17
0 0 0 0 28
0 0 0 0 35

Minimum possible range is 35. Oh got the trick.

But my question is If I am thrown a question like this in the test I might panic & try many different kind of values. Is there a particular strategy or pattern for this type of questions.


Try to look at it as overlapping sets problem:
# of people in group A is 17;
# of people in group B is 28;
# of people in group C is 35;

What is the minimum # of total people possible in all 3 groups? Clearly if two smaller groups A and B are subsets of bigger group C (so if all people who are in A are also in C and all people who are in B are also in C), then total # of people in all 3 groups will be 35. Minimum # of total people can not possibly be less than 35 since there are already 35 people in group C.

Answer: C.

Hope it's clear.

P.S. Notice that max range for the original question is not limited when the max # of people in all 3 groups for revised question is 17+28+35 (in case there is 0 overlap between the 3 groups).


Sorry Bunuel but I am still not convinced by this explanation..... for example if you have the following votes:

1 1 1 1 18
1 1 1 1 29
4 4 4 4 39

You would have range 35 for third group, but the range of all three groups would be 39-1= 38 > 35 ?
what am I missing?
Thanks


The question asks: what is the MINIMUM possible range in scores of the three test-takers? The range could be 38, or 56, or 119 (or any other number for certain conditions)... but it CANNOT be less than 35, so the MINIMUM possible range is 35.
Intern
Intern
Joined: 04 Sep 2021
Posts: 2
Own Kudos [?]: 1 [0]
Given Kudos: 25
Location: India
Send PM
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
KarishmaB
Cant there be negative marking in case of calculating max range
GMAT Club Bot
Re: Three people each took 5 tests. If the ranges of their score [#permalink]
 1   2   
Moderators:
Math Expert
92904 posts
Senior Moderator - Masters Forum
3137 posts

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