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.
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:
Enter The Economist GMAT Tutor’s Brightest Minds competition – it’s completely free! All you have to do is take our online GMAT simulation test and put your mind to the test. Are you ready? This competition closes on December 13th.
Attend a Veritas Prep GMAT Class for Free. With free trial classes you can work with a 99th percentile expert free of charge. Learn valuable strategies and find your new favorite instructor; click for a list of upcoming dates and teachers.
Does GMAT RC seem like an uphill battle? e-GMAT is conducting a free webinar to help you learn reading strategies that can enable you to solve 700+ level RC questions with at least 90% accuracy in less than 10 days.
Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
Updated on: 07 Aug 2018, 01:25
3
17
00:00
A
B
C
D
E
Difficulty:
75% (hard)
Question Stats:
65% (03:35) correct 35% (03:37) wrong based on 269 sessions
HideShow timer Statistics
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
29 Jan 2017, 12:42
2
3
Hey,
PFB the official solution.
Given
• Average score of the group \(= 50\)
o So, total score of the group \(= 50*5 = 250\)
To Find:
• Range of the scores of the group
o Range of the score = Highest score – Lowest Score
Working Out
1. Let Alastair’s score be \(x\)……….(1)
2. Darren’s Score
a. We know that, Alastair’s score = \(\frac{1}{2}\) * Darren’s Score b. So, Darren’s score \(= 2x\)………..(2)
3. Cook’s Score
a. Now, we know that Darren’s Score = Cook’s score +\(\frac{1}{5} *\) Cook’s score b. So, we can write \(2x =\frac{6}{5}\) * Cook’s score c. So, Cook’s score \(= \frac{5x}{3}\)………..(3)
4. Bell’s Score
a. We know that Darren’s Score \(= \frac{3}{2}\) * Bell’s score b. So, we can write \(2x = \frac{3}{2}\) * Bell’s score c. Bell’s score \(= \frac{4x}{3}\)……(4)
5. Eoin’s Score
a. We know that Eoin’s score = Cook’s score \(+ \frac{2}{5}\) * Cook’s score b. So, we can write Eoin’s score \(= \frac{7x}{3}\) ……….(5)
6. Also, sum of all the scores \(= 250\)
a. \(x + 2x + \frac{5x}{3} + \frac{4x}{3} + \frac{7x}{3} = 250\) b. \(x = 30\) c. Hence, the difference between the highest and the lowest score \(= \frac{7x}{3} – x = 70 – 30 = 40\)
So, the range of the scores of the group is \(40\).
Register for our Free Session on Number Properties (held every 3rd week) to solve exciting 700+ Level Questions in a classroom environment under the real-time guidance of our Experts
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
22 Aug 2018, 04:08
1
EgmatQuantExpert wrote:
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
A. 25 B. 30 C. 35 D. 40 E. 50
To determine the ratio of the scores, plug in numbers and reduce the resulting ratio as much as possible. Let A = Alastair, B = Bell, C = Cook, D = Darren, and E = Eoin. Let B = the product of the denominators = 2*5*5*2 = 100.
Darren’s score was 3/2 times that of Bell’s score. D = 3/2(B) = (3/2)(100) = 150.
Alastair scored exactly 1/2 of Darren’s score. A = (1/2)D = (1/2)(150) = 75.
Darren’s score was 1/5th more than Cook’s score. In other words, Darren's score of 150 is 6/5 Cook's score: 150 = (6/5)C C = (5/6)150 = 125.
Eoin scored 2/5th more than Cook. In other words, Eoin's score is 7/5 Cook's score of 125: E = (7/5)125 = 175.
A : B : C : D : E = 75:100:125:150:175 = 3:4:5:6:7. When the values in the ratio are fully reduced, biggest - smallest = 7-3 = 4. Implication: The range of the values must be a MULTIPLE OF 4.
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
22 Jan 2017, 15:08
4
1
Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
A. 25 B. 30 C. 35 D. 40 E. 50
the 5 scores form a progression: C-2/5, C-1/5, C, C+1/5, C+2/5 if C=50, then progression is 30, 40, 50, 60, 70 range=70-30=40 D
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
22 Jan 2017, 06:39
EgmatQuantExpert wrote:
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
A. 25 B. 30 C. 35 D. 40 E. 50
IMO, the Answer is B..The explanation is as follows. Consider the scores of Alastair to be A, Bell to be B, Cook to be C,Darren to be D and Eoin to be E. Given:-
A=1/2D C=D-1/5 B=2/3D E=D+1/5
Since average is 50. Summing A,B,C,D and E and taking average gives us value of D to be sixty.
Hence the lowest value in the set =1/2D=30 Biggest value in the set=D+1/5=60.2 Hence range =60.2- 30=30.2..which is approximated to 30. Hence answer is Option B
Register for our Free Session on Number Properties (held every 3rd week) to solve exciting 700+ Level Questions in a classroom environment under the real-time guidance of our Experts
Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
Updated on: 07 Aug 2018, 02:45
adityapareshshah wrote:
EgmatQuantExpert wrote:
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
A. 25 B. 30 C. 35 D. 40 E. 50
IMO, the Answer is B..The explanation is as follows. Consider the scores of Alastair to be A, Bell to be B, Cook to be C,Darren to be D and Eoin to be E. Given:-
A=1/2D C=D-1/5 B=2/3D E=D+1/5
Since average is 50. Summing A,B,C,D and E and taking average gives us value of D to be sixty.
Hence the lowest value in the set =1/2D=30 Biggest value in the set=D+1/5=60.2 Hence range =60.2- 30=30.2..which is approximated to 30. Hence answer is Option B
Hey,
There are two things, which I want to point out -
1. The final value of A, B, C, D and E are all integers. So we don't need to approximate anything.
2. Also, the relation between C and D and a few others are not written correctly. Let me take an example -
"Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score"
This line means - D = C + \(\frac{1}{5}\)*C D = \(\frac{6C}{5}\)
Similarly, check the other ratios once. I am sure you will figure out the minor errors.
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
25 Feb 2017, 12:39
Not a hard question but lot's of computation involved. I don't see how this can be done carefully in 2 minutes. Just reading, understanding, and planning how to attack this question takes a solid minute. Then there is a good 2-3 minutes of math involved (5 equations, then combining them, then solving for the variable, then determining the range).
Would it be fair to say that the GMAT likely wouldn't have a question this math heavy? Or is there a shortcut? Would questions like this typically have a shortcut? How long did it take people to solve this?
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
05 Apr 2017, 17:18
EgmatQuantExpert wrote:
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
This problem looks a lot worse than it is. Solved for C, used decimals instead of fractions, and ignored A and B until the end (b/c the way the question is written suggests C as jumping off point).
Stage I
A = \(\frac{1}{2}\)D
B = ??
C = ??
D = \(\frac{1}{5}\) more than C = 1.2C
E = \(\frac{2}{5}\) more than C = 1.4C ----- Stage II
2 of 5 variables are in terms of C. Add C itself, and that's 3 of 5.
A and B in terms of C? ----- A = \(\frac{1}{2}\)or .5D.
D = 1.2C.
1.2C x .5 = .6C ----- B is hardest.
D = 1.5B. D also = 1.2C
1.5B = 1.2C
B = \(\frac{1.2}{1.5}\)C = \(\frac{12}{15}\)C = \(\frac{4}{5}\)C = .8C --- Stage III --Now the list is
A = .6C B = .8C C = 1.0C D = 1.2C E = 1.4C
And now there's an evenly spaced set/progression where median = mean, so C = 50.
Largest - smallest = range. E is 1.5 x 50 = 70. A is .6 x 50 = 30.
Range is 70 - 30 = 40. Answer D
_________________
SC Butler has resumed! Get two SC questions to practice, whose links you can find by date, here.
Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has -- Margaret Mead
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
11 Apr 2017, 15:05
EgmatQuantExpert wrote:
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
17 Aug 2017, 09:43
EgmatQuantExpert wrote:
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
A. 25 B. 30 C. 35 D. 40 E. 50
From the question; A=1/2D D=6/5C E=7/5C B=2/3D
Looking at the average (=50) and answer choices (25,30,35,40,40) it is clear that all the scores are multiples of 5.. Now D is also a multiple of 6... So, D can be 6*5=30 or 6*5*2=60...as average is 50 and D is better than A,B and C...60 seems better Assume D=60...We get E=70, B=40, A=30, C=50....and voila...the avg is 50... So, range is 70-30=40
We can also take E..which is a multiple of 7 and 5...so probably 35 or 70..as E is highest..it is greater than 50...So take 70 again we get D=60, B=40, A=30, C=50..
Testing the values comes with practice...and by scanning the information and answer choices..but it does wonders
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
02 Jan 2018, 22:49
EgmatQuantExpert wrote:
Q.) Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an aptitude test. Alastair scored exactly \(\frac{1}{2}\)of Darren’s score, whose score was \(\frac{1}{5}\)th more than Cook’s score. Eoin scored \(\frac{2}{5}\)th more than Cook and Darren’s score was \(\frac{3}{2}\) times that of Bell’s score. If the average score (arithmetic mean) of the group was 50, what was the range of the scores of the group?
Register for our Free Session on Number Properties (held every 3rd week) to solve exciting 700+ Level Questions in a classroom environment under the real-time guidance of our Experts
First, I just wrote down all of what I could extract from the question. A = (1/2)D D = (1 + 1/5)C = (6/5)C E = (1 + 2/5)C = (7/5)C => C = (5/7)E D= (3/2)B
=> A = (1/2)D = (1/2)x(6/5)C= (1/2)x(3/2)B = (1/2)x(6/5)x(5/7)E
=> A = (1/2)D = (3/5)C = (3/4)B = (3/7)E
=> A : D : C : B : E = 1 : 2 : 5/3 : 4/3 : 7/3
OR we could say: A : D : C : B : E = 3 : 6 : 5 : 4 :7
From the above ratio, we can conclude that the range of the score would be the difference between A & E. The range would be equal to (50x5:18)x(7-3) = 40. Answer D.
Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
22 Aug 2018, 05:22
Krishaa12 wrote:
Payal mam how should I represent "if question was asked...... Eoin scored 2/5 th of Cook" ..?please help
Hey Krishaa12, Let me put the representations of both the statements: the one given in the question and the new statement that you mentioned.
Given that, "Eoin scored \(\frac{2}{5}\)th more than Cook." Hence, we can write Eoin's score = Cook’s score + \(\frac{2}{5}\) * Cook’s score
However, if the statement says "Eoin scored \(\frac{2}{5}\)th of what Cook scored" Then we could have written it as Eoin's score = \(\frac{2}{5}\) * Cook’s score
Re: Five friends Alastair, Bell, Cook, Darren and Eoin appeared in an apti
[#permalink]
Show Tags
31 Oct 2019, 09:18
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.
_________________
close
65% (03:35) correct 
