It is currently 15 Dec 2017, 10:12

# Decision(s) Day!:

CHAT Rooms | Olin (St. Louis) R1 | Tuck R1 | Ross R1 | Fuqua R1

### 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

# A certain portfolio consisted of 5 stocks, priced at \$20,

Author Message
TAGS:

### Hide Tags

Current Student
Joined: 11 May 2008
Posts: 554

Kudos [?]: 232 [2], given: 0

A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

19 Jul 2008, 23:15
2
KUDOS
26
This post was
BOOKMARKED
00:00

Difficulty:

95% (hard)

Question Stats:

58% (02:07) correct 42% (02:51) wrong based on 379 sessions

### HideShow timer Statistics

A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45 and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

A. 20, 35, 70
B. 20, 45, 70
C. 20, 35, 40
D. 35, 40, 70
E. 35, 40, 45
[Reveal] Spoiler: OA

Kudos [?]: 232 [2], given: 0

Current Student
Joined: 12 Jun 2008
Posts: 287

Kudos [?]: 59 [8], given: 0

Schools: INSEAD Class of July '10
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

20 Jul 2008, 00:44
8
KUDOS
1
This post was
BOOKMARKED
Make the smallest decrease and the highest increase, and you have:

- for the smallest: 35% of \$20 = \$7 decrease
- for the highest: 15% of \$70 = \$10.5 increase

==> maximum increase of the portfolio is \$3.5 total

Total value of the portfolio was \$20+\$35+\$40+\$45+\$70 = \$210

So the maximun increase corresponds to 3.5/210 = 1.7%

You cannot be closer to 2%, thus it is \$20 that decrease and \$70 that increase

Kudos [?]: 59 [8], given: 0

Retired Moderator
Joined: 18 Jul 2008
Posts: 959

Kudos [?]: 313 [0], given: 5

Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

21 Jul 2008, 04:31
How did you know which price to increase and decrease?

Is it by process of elimination (trying each one by one), or is there a quicker method.

Oski wrote:
Make the smallest decrease and the highest increase, and you have:

- for the smallest: 35% of \$20 = \$7 decrease
- for the highest: 15% of \$70 = \$10.5 increase

==> maximum increase of the portfolio is \$3.5 total

Total value of the portfolio was \$20+\$35+\$40+\$45+\$70 = \$210

So the maximun increase corresponds to 3.5/210 = 1.7%

You cannot be closer to 2%, thus it is \$20 that decrease and \$70 that increase

Kudos [?]: 313 [0], given: 5

Manager
Joined: 04 Apr 2008
Posts: 215

Kudos [?]: 39 [0], given: 3

Location: Pune
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

21 Jul 2008, 05:05
generally we start with the midlle terms and then you move on one side......But depends upon the experience that one selects the limits.....POE
_________________

Every Problem Has a Sloution So keep working
AB

Kudos [?]: 39 [0], given: 3

Current Student
Joined: 12 Jun 2008
Posts: 287

Kudos [?]: 59 [1], given: 0

Schools: INSEAD Class of July '10
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

21 Jul 2008, 14:09
1
KUDOS
How did you know which price to increase and decrease?

Is it by process of elimination (trying each one by one), or is there a quicker method.

I decreased the minimum and increased the maximum, therefore the gap I got is the biggest we can get. And it is still not sufficient to reach the 2% mark : so this is the answer.

A more general method if you do not see it from the begining is as follow :

- compute 2% of the total (here 210*2% = 4.2)

- write down the five numbers and compute for each one what it means to increase it by 15% or decrease it by 35%

20 : +3 ; -7
35 : +5.25 ; -12.25
40 : +6 ; -14
45 : +6.75 ; -15.75
70 : +10.5 ; -24.5

- then, "play" with the 10 numbers you get to be as close as possible to this 4.2

Kudos [?]: 59 [1], given: 0

Manager
Joined: 11 Mar 2008
Posts: 110

Kudos [?]: 28 [0], given: 0

A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

04 Dec 2008, 17:25
4
This post was
BOOKMARKED
A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45 and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

A. 20, 35, 70
B. 20, 45, 70
C. 20, 35, 40
D. 35, 40, 70
E. 35, 40, 45

Kudos [?]: 28 [0], given: 0

SVP
Joined: 29 Aug 2007
Posts: 2470

Kudos [?]: 868 [1], given: 19

Re: Statistics: % and logic [#permalink]

### Show Tags

04 Dec 2008, 22:07
1
KUDOS
snaps wrote:
A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45 and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

A) 20, 35, 70
B) 20, 45, 70
C) 20, 35, 40
D) 35, 40, 70
E) 35, 40, 45

E) 35, 40, 45

It has to be E cuz the 2% of of the portfolio is approx 4.00 and the diff between 15% of 70 and 35% of 20 = 3.50. so this is the most closest.
_________________

Gmat: http://gmatclub.com/forum/everything-you-need-to-prepare-for-the-gmat-revised-77983.html

GT

Kudos [?]: 868 [1], given: 19

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 7800

Kudos [?]: 18136 [31], given: 236

Location: Pune, India
Re: Statistics: % and logic [#permalink]

### Show Tags

18 Jul 2011, 20:49
31
KUDOS
Expert's post
12
This post was
BOOKMARKED
snaps wrote:
A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45 and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

A) 20, 35, 70

B) 20, 45, 70

C) 20, 35, 40

D) 35, 40, 70

E) 35, 40, 45

Use logic and the calculations involved will be negligible.
Since we have been given that there is an overall increase, the increase should be greater than the decrease. So
15% of A > 35% of B

Now think that 15% of A will be equal to 30% of B if A is twice of B. But 15% of A is greater than 30% of B so A must be greater than twice of B. In fact 15% of A is greater than 35% of B so A must be substantially greater than twice of B. So B has to be 20 because we have values more than twice of 20 (which are 45 and 70). We don't have any values which are more than twice of any other given number (30, 35, 40, 70).

A can be 45 or 70. I would bet on 70 since A has be substantially greater than twice of 20.
Even if I want to confirm, 10% of 20 is 2 so 30% of 20 is 6. 5% of 20 is 1 so 35% of 20 is 7.
15% of A has to be greater than 7. Only 70 satisfies this since 10% of 70 is 7.
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for \$199

Veritas Prep Reviews

Kudos [?]: 18136 [31], given: 236

Senior Manager
Joined: 23 Jun 2009
Posts: 360

Kudos [?]: 134 [1], given: 80

Location: Turkey
Schools: UPenn, UMich, HKS, UCB, Chicago

### Show Tags

19 Nov 2011, 11:44
1
KUDOS
1
This post was
BOOKMARKED
enigma123 wrote:
A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45, and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another stock decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

(A) \$20, \$35, and \$70
(B) \$20, \$45, and \$70
(C) \$20, \$35, and \$40
(D) \$35, \$40, and \$70
(E) \$35, \$40, and \$45

This is a pure trial and error question. You should try 5*4 options.

But there may be a short cut.
Increase of one by 15% and decrease of other buy 35% means a little increase. Thus, the increasing one must be at least 2,3 times of the decreasing one. There is only one probability that is 20 and 70. 70*0,15-20*0,35=3,5 is 1,7 percent of original sum.

That is to say, answer is E.

Kudos [?]: 134 [1], given: 80

Senior Manager
Joined: 23 Jun 2009
Posts: 360

Kudos [?]: 134 [0], given: 80

Location: Turkey
Schools: UPenn, UMich, HKS, UCB, Chicago

### Show Tags

20 Nov 2011, 05:27
Lets try.

There is a 15% increase in one number and a 35% decrease in other number. But the result is a total increase in sum. This means 15% of a number is slightly bigger that 35%of other number in the set. There is only one possibility for this. That is 70 and 20.

Kudos [?]: 134 [0], given: 80

Director
Joined: 25 Apr 2012
Posts: 721

Kudos [?]: 873 [1], given: 724

Location: India
GPA: 3.21
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

03 Dec 2013, 01:50
1
KUDOS
snaps wrote:
A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45 and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

A. 20, 35, 70
B. 20, 45, 70
C. 20, 35, 40
D. 35, 40, 70
E. 35, 40, 45

Sum of price of all stocks : \$ 210
Avg price : \$ 42

The average price of the stock goes up by 2% of Avg stock price which is \$ 0.84-------> This indicates the total increase in the sum is 0.84*5 = \$ + 4.20

from the Q we can say that since the avg stock price has gone up therefore 0.15A - 0.35B >0. A has to be greater than B and thus we have

or 0.15A- 0.35B ~ 4.2\$
Now 35% of 20 = 7 and 15% of 70 = 10.5 Diff : 3.5
0.15*35 = ~ 5.25 and 15 % of 70 =10.5 Diff: ~ 5
0.15*35= 5.25. and 15% of 45 = 6.75, Diff~ 1.5

For any other combination
ex B = 35 and 0.35 B = 12.25 and A =0.15*70 = 10.5 and the difference between A and B is negative and as B increase the the difference of A and B will become more negative.

Hence Ans option E. The values which are constant

_________________

“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

Kudos [?]: 873 [1], given: 724

Current Student
Joined: 06 Sep 2013
Posts: 1965

Kudos [?]: 759 [1], given: 355

Concentration: Finance
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

20 Mar 2014, 08:36
1
KUDOS
Or one can use differentials

13x - 37y = 0 therefore X is close to 3 times Y

So the only possibilities that even comes close to this is that X = 70 and Y=20

Therefore, the stocks that remain unchanged are the middle three values: 35, 40,45

Hope this clarifies
Cheers
J

Kudos [?]: 759 [1], given: 355

Retired Moderator
Joined: 17 Sep 2013
Posts: 387

Kudos [?]: 354 [0], given: 139

Concentration: Strategy, General Management
GMAT 1: 730 Q51 V38
WE: Analyst (Consulting)
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

24 Mar 2014, 03:53
snaps wrote:
A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45 and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

A. 20, 35, 70
B. 20, 45, 70
C. 20, 35, 40
D. 35, 40, 70
E. 35, 40, 45

Average is 42
2%= .8 (App)
Total in Increase in the portfolio is 4 ( As each stock increases by 0.8 => 5 x 0.8)

Difference between the varying stock prices should be 4

Lets take the first and the most conservative case: 22 decreases by 35% = 7.7
A corresponding increase in a stock price of approx 11 is required to bring the difference in stock prices to 4
We can quickly conclude that 70 ( 7 x 15= 10.5) is as good as it gets...coz any stock other than 22 will have an even greater numerical decrease with a 35% decline in its value and has no share that can maintain the difference of 4 ...as we have already taken the highest increase of 15% in 70
_________________

Appreciate the efforts...KUDOS for all
Don't let an extra chromosome get you down..

Kudos [?]: 354 [0], given: 139

Manager
Joined: 28 Jul 2013
Posts: 85

Kudos [?]: 45 [0], given: 37

Location: India
Concentration: Marketing, Strategy
GPA: 3.62
WE: Engineering (Manufacturing)
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

05 Apr 2014, 08:39
@jlgdr: you mean 15x-35y>0

hence (x/y)>(7/3)
when you put x = 70 and y = 20 this equation is satisfied. here x/y is 7/2 > 7/3

Kudos [?]: 45 [0], given: 37

Current Student
Joined: 06 Sep 2013
Posts: 1965

Kudos [?]: 759 [0], given: 355

Concentration: Finance
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

01 May 2014, 07:18
sayansarkar wrote:
@jlgdr: you mean 15x-35y>0

hence (x/y)>(7/3)
when you put x = 70 and y = 20 this equation is satisfied. here x/y is 7/2 > 7/3

Not so. Its supposed to be 37y by concept of differentials. See if price of total average rose by 2% and the price of one of the components declined by 35% then the difference is -35--2 = 35+2 = 37

Is this clear?

Cheers
J

Kudos [?]: 759 [0], given: 355

Intern
Joined: 02 Jun 2015
Posts: 33

Kudos [?]: 18 [0], given: 34

Location: United States
Concentration: Operations, Technology
GMAT Date: 08-22-2015
GPA: 3.92
WE: Science (Other)
A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

19 Aug 2015, 10:08
jlgdr wrote:
13x - 37y = 0 therefore X is close to 3 times Y

The above conjecture is incorrect. The right side of the equation is not 0, so making any assumption about the ratio x/y would be poor.

Generalizing the problem we get that a high (H) stock has to increase by 15% and a low (L) stock has to decrease by 35%. (H > L)

Formula looks like: .02*(H + L + Others) = .15*H - .35*L which we can rewrite as .02*Others = .13*H - .37*L.

If the "Other" stocks did not exist you could make an assumption about the ratio of H/L, but since they do, H/L isn't necessarily close to 3.

Kudos [?]: 18 [0], given: 34

Manager
Joined: 09 Jan 2016
Posts: 134

Kudos [?]: 97 [0], given: 59

GPA: 3.4
WE: General Management (Human Resources)
Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

08 May 2017, 23:50
arjtryarjtry wrote:
A certain portfolio consisted of 5 stocks, priced at \$20, \$35, \$40, \$45 and \$70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?

A. 20, 35, 70
B. 20, 45, 70
C. 20, 35, 40
D. 35, 40, 70
E. 35, 40, 45

15% of A = 35% of B. given that the average price of a stock in the portfolio rose by approximately 2%.That means A is slightly more than twice of B.
35% of 20 is 7 and 15% of 70 is 10.5.thus choice E matches.

Kudos [?]: 97 [0], given: 59

Intern
Joined: 16 Feb 2017
Posts: 27

Kudos [?]: 14 [0], given: 80

Re: A certain portfolio consisted of 5 stocks, priced at \$20, [#permalink]

### Show Tags

12 Sep 2017, 08:27
Oski wrote:
How did you know which price to increase and decrease?

Is it by process of elimination (trying each one by one), or is there a quicker method.

I decreased the minimum and increased the maximum, therefore the gap I got is the biggest we can get. And it is still not sufficient to reach the 2% mark : so this is the answer.

A more general method if you do not see it from the begining is as follow :

- compute 2% of the total (here 210*2% = 4.2)

- write down the five numbers and compute for each one what it means to increase it by 15% or decrease it by 35%

20 : +3 ; -7
35 : +5.25 ; -12.25
40 : +6 ; -14
45 : +6.75 ; -15.75
70 : +10.5 ; -24.5

- then, "play" with the 10 numbers you get to be as close as possible to this 4.2

Only 15% gain of 70 and -35% (depreciation) of 20 shall together provide an increase of 2% to all stock options.
Rest all combinations shall provide negative value as in table

+15% -35%

20 : +3 -7
35 : +5.25 -12.25
40 : +6 -14
45 : +6.75 -15.75
70 : +10.5 -24.5

Kudos [?]: 14 [0], given: 80

Re: A certain portfolio consisted of 5 stocks, priced at \$20,   [#permalink] 12 Sep 2017, 08:27
Display posts from previous: Sort by