Yesterday's closing prices of 2,420 different stocks listed : GMAT Problem Solving (PS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 18 Jan 2017, 15:07

### 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

# Yesterday's closing prices of 2,420 different stocks listed

Author Message
TAGS:

### Hide Tags

Manager
Joined: 23 Aug 2011
Posts: 83
Followers: 3

Kudos [?]: 200 [10] , given: 13

Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

14 Sep 2012, 21:18
10
KUDOS
42
This post was
BOOKMARKED
00:00

Difficulty:

45% (medium)

Question Stats:

67% (02:52) correct 33% (02:05) wrong based on 1342 sessions

### HideShow timer Statistics

Yesterday's closing prices of 2,420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent greater than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

(A) 484
(B) 726
(C) 1,100
(D) 1,320
(E) 1,694

[Reveal] Spoiler:
Source :OG-13; Q71(PS)

Folks, please write the answer with all the steps. The answer is clear cut but the only thing I'm interested in is the interpretation of the word problem and the respective approach to solve it. Thanks.
If any body used tabular approach, i will be glad to see it because i had trouble solving this problem with the same.
[Reveal] Spoiler: OA

_________________

Whatever one does in life is a repetition of what one has done several times in one's life!
If my post was worth it, then i deserve kudos

Last edited by Bunuel on 15 Sep 2012, 01:23, edited 1 time in total.
Edited the question.
Senior Manager
Joined: 11 May 2011
Posts: 372
Location: US
Followers: 3

Kudos [?]: 95 [9] , given: 46

Re: Yesterday's closing prices of 2420different stocks listed on [#permalink]

### Show Tags

14 Sep 2012, 22:36
9
KUDOS
3
This post was
BOOKMARKED
Lets consider the below -
The number of stocks that closed at a higher price = H
The number of stocks that closed at a lower price = L
We understand from first statement -> H+L = 2420 ----(1)
We understand from second statement -> H = (120/100)L => H = 1.2L ----(2)

Solve eq (1) & (2) to get H = 1320.

Questions, Pls let me know. Cheers!
_________________

-----------------------------------------------------------------------------------------
What you do TODAY is important because you're exchanging a day of your life for it!
-----------------------------------------------------------------------------------------

Manager
Joined: 02 Jun 2011
Posts: 114
Followers: 0

Kudos [?]: 43 [12] , given: 5

Re: Yesterday's closing prices of 2420different stocks listed on [#permalink]

### Show Tags

15 Sep 2012, 00:18
12
KUDOS
1
This post was
BOOKMARKED
conty911 wrote:
Yesterday's closing prices of 2420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price than yesterday was 20% greater than number that closed at lower price.How many of the stocks closed at a higher price than yesterday?

a)484
b)726
c)1100
d)1320
e)1694

Source :OG-13; Q71(PS)

Folks, please write the answer with all the steps. The answer is clear cut but the only thing I'm interested in is the interpretation of the word problem and the respective approach to solve it. Thanks.
If any body used tabular approach, i will be glad to see it because i had trouble solving this problem with the same.

No. of share closed at higher price than yesterday = X
No. of share closed at lower price than yesterday = Y
X = 1.2Y
so,
1.2Y + Y = 2420
Y = 1100

So, X = 1320

If you like explaination kindly give kudos
Math Expert
Joined: 02 Sep 2009
Posts: 36548
Followers: 7077

Kudos [?]: 93108 [15] , given: 10552

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

15 Sep 2012, 01:37
15
KUDOS
Expert's post
9
This post was
BOOKMARKED
Yesterday's closing prices of 2,420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent greater than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

(A) 484
(B) 726
(C) 1,100
(D) 1,320
(E) 1,694

APPROACH #1:

Say $$x$$ is the number of stocks that closed at a lower price, then $$1.2x$$ is the number of stocks that closed at a higher price. Since the total number of stocks is 2,420, then $$x+1.2x=2,420$$ --> $$x=1,100$$, so $$1.2x=1,320$$.

APPROACH #2:

If the number of stocks that closed at a lower price were the same as the number of stocks that closed at a higher price, then the number of stocks that closed at a higher price would be 2,420/2=1,210. Since we know that more stocks closed at a higher price than at a lower price than the answer must be greater than 1,210: eliminate A, B, and C. Now, E cannot be correct, because in this case 1,694 closed at a higher price and ~700 closed at a lower price, but 1,694 is obviously not 20% greater than ~700, so we are left with D.

Hope it's clear.
_________________
Intern
Joined: 09 Jun 2012
Posts: 13
Followers: 0

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

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

21 Sep 2012, 09:38
Let number of shares closed at lower price be x. Hence closed at higher price is 1.2 (this is 20% greater than closed at lower price).
x+1.2x = 2420 => x = 1100
Hence shares closed at higher price = 1.2x = 1320 (D)
Intern
Joined: 18 Jan 2013
Posts: 3
Followers: 0

Kudos [?]: 2 [1] , given: 3

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

04 May 2013, 14:15
1
KUDOS
Can someone please help....The way this problem has been solved is correct...I arrived upon the same answer by the process of elimination but when I initially tired I used the following technique:

Total percentage of stocks = 100%
All stocks changed value....therefore H + L = 100
Given that 20% stocks closed higher than those that closed lower hence H - L = 20

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Naren
Manager
Joined: 09 Apr 2013
Posts: 214
Location: United States
Concentration: Finance, Economics
GMAT 1: 710 Q44 V44
GMAT 2: 740 Q48 V44
GPA: 3.1
WE: Sales (Mutual Funds and Brokerage)
Followers: 4

Kudos [?]: 77 [1] , given: 40

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

04 May 2013, 14:43
1
KUDOS
tsnarendran wrote:
Can someone please help....The way this problem has been solved is correct...I arrived upon the same answer by the process of elimination but when I initially tired I used the following technique:

Total percentage of stocks = 100%
All stocks changed value....therefore H + L = 100
Given that 20% stocks closed higher than those that closed lower hence H - L = 20

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Naren

The correct ratio is closer to 55% - 45% not 60% - 40%

The 20% isn't based off of the total amount of stocks, it's based off of the amount that closed higher vs those that closed lower... so rather than there being a difference of 20% of the TOTAL (60-40) there's a difference of 20% of each position which is closer to only 10% of the total.
Intern
Joined: 18 Jan 2013
Posts: 3
Followers: 0

Kudos [?]: 2 [1] , given: 3

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

04 May 2013, 15:03
1
KUDOS
dave785 wrote:
tsnarendran wrote:
Can someone please help....The way this problem has been solved is correct...I arrived upon the same answer by the process of elimination but when I initially tired I used the following technique:

Total percentage of stocks = 100%
All stocks changed value....therefore H + L = 100
Given that 20% stocks closed higher than those that closed lower hence H - L = 20

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Naren

The correct ratio is closer to 55% - 45% not 60% - 40%

The 20% isn't based off of the total amount of stocks, it's based off of the amount that closed higher vs those that closed lower... so rather than there being a difference of 20% of the TOTAL (60-40) there's a difference of 20% of each position which is closer to only 10% of the total.

When you say that the 20% is based off of the amount that closed higher vs that closed lower.....did all stocks not change value??..so 100% changed values right? so 20% of 100% right...am sorry...I am usually not this confused...but here I am....I am waiting for that ahaa moment I guess and it all becomes clear...

any help is greatly appreciated...
Manager
Joined: 09 Apr 2013
Posts: 214
Location: United States
Concentration: Finance, Economics
GMAT 1: 710 Q44 V44
GMAT 2: 740 Q48 V44
GPA: 3.1
WE: Sales (Mutual Funds and Brokerage)
Followers: 4

Kudos [?]: 77 [2] , given: 40

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

04 May 2013, 16:42
2
KUDOS
tsnarendran wrote:
dave785 wrote:
tsnarendran wrote:
Can someone please help....The way this problem has been solved is correct...I arrived upon the same answer by the process of elimination but when I initially tired I used the following technique:

Total percentage of stocks = 100%
All stocks changed value....therefore H + L = 100
Given that 20% stocks closed higher than those that closed lower hence H - L = 20

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Naren

The correct ratio is closer to 55% - 45% not 60% - 40%

The 20% isn't based off of the total amount of stocks, it's based off of the amount that closed higher vs those that closed lower... so rather than there being a difference of 20% of the TOTAL (60-40) there's a difference of 20% of each position which is closer to only 10% of the total.

When you say that the 20% is based off of the amount that closed higher vs that closed lower.....did all stocks not change value??..so 100% changed values right? so 20% of 100% right...am sorry...I am usually not this confused...but here I am....I am waiting for that ahaa moment I guess and it all becomes clear...

any help is greatly appreciated...

the question states that there are 20% more stocks that closed higher today than stocks that closed lower today.

Stocks cannot close both higher and lower. Therefore the 20% increase is not based off of the total amount, only off of the amount that closed higher...

Therefore, (100% stocks that closed lower tody ) + (120% stocks that closed lowertoday) = 100% of ALL stocks (2420)

You're reading the question as if it read 20% more stocks closed higher today than closed higher yesterday... in which case the answer would be unsolvable because we don't know how many closed higher yesterday.
Intern
Joined: 11 Nov 2013
Posts: 1
Followers: 0

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

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

11 Nov 2013, 12:17
Can someone please explain how to get 1.2x? Where does 1.2 come from/ how do you calculate that??
Math Expert
Joined: 02 Sep 2009
Posts: 36548
Followers: 7077

Kudos [?]: 93108 [2] , given: 10552

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

12 Nov 2013, 10:01
2
KUDOS
Expert's post
squirecreamsicle wrote:
Can someone please explain how to get 1.2x? Where does 1.2 come from/ how do you calculate that??

We are told that "the number of stocks that closed at a higher price today than yesterday was 20 percent greater than the number that closed at a lower price".

20 percent greater is 1.2 times as many. So, if $$x$$ is the number of stocks that closed at a lower price, then $$1.2x$$ is the number of stocks that closed at a higher price.

Hope it's clear.
_________________
Intern
Joined: 19 Jan 2014
Posts: 31
Followers: 0

Kudos [?]: 16 [0], given: 51

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

21 Feb 2014, 15:06
I'm having a huge problem understanding the solution for some reason. I do not understand why 1.2x+x=2420

So there are 2 420 stocks. Yesterday X were sold at lower price and Y and higher price.

So today I know that stocks sold at a higher price are 20 percent more than stocks sold at a lower price yesterday. Which would indeed give me 1.2X but! Don't I need to have another unknown? 1.2X + z = 2 420. as Z would represent number of stocks sold at higher price today. So I do not see why we get 1.2x + x as we did not use X for today's number of stocks sold at lower price.

I must be missing the important point. If someone could explain I'd be very thankful.
Math Expert
Joined: 02 Sep 2009
Posts: 36548
Followers: 7077

Kudos [?]: 93108 [2] , given: 10552

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

22 Feb 2014, 02:31
2
KUDOS
Expert's post
bytatia wrote:
I'm having a huge problem understanding the solution for some reason. I do not understand why 1.2x+x=2420

So there are 2 420 stocks. Yesterday X were sold at lower price and Y and higher price.

So today I know that stocks sold at a higher price are 20 percent more than stocks sold at a lower price yesterday. Which would indeed give me 1.2X but! Don't I need to have another unknown? 1.2X + z = 2 420. as Z would represent number of stocks sold at higher price today. So I do not see why we get 1.2x + x as we did not use X for today's number of stocks sold at lower price.

I must be missing the important point. If someone could explain I'd be very thankful.

There are total of 2,420 stocks, out of them the number of stocks that closed at a higher price than yesterday was 20% greater than number that closed at lower price.

Say $$x$$ is the number of stocks that closed at a lower price TODAY, then $$1.2x$$ is the number of stocks that closed at a higher price TODAY. Since the total number of stocks is 2,420, then $$x+1.2x=2,420$$ --> $$x=1,100$$, so $$1.2x=1,320$$.

Hope it's clear.
_________________
Intern
Joined: 21 May 2014
Posts: 12
Followers: 0

Kudos [?]: 2 [0], given: 24

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

06 Jun 2014, 16:49
tsnarendran wrote:
Can someone please help....The way this problem has been solved is correct...I arrived upon the same answer by the process of elimination but when I initially tired I used the following technique:

Total percentage of stocks = 100%
All stocks changed value....therefore H + L = 100
Given that 20% stocks closed higher than those that closed lower hence H - L = 20

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Naren

dave785 wrote:
the question states that there are 20% more stocks that closed higher today than stocks that closed lower today.

Stocks cannot close both higher and lower. Therefore the 20% increase is not based off of the total amount, only off of the amount that closed higher...

Therefore, (100% stocks that closed lower tody ) + (120% stocks that closed lowertoday) = 100% of ALL stocks (2420)

You're reading the question as if it read 20% more stocks closed higher today than closed higher yesterday... in which case the answer would be unsolvable because we don't know how many closed higher yesterday.

I just made the same mental error, so I just wanted to thank tsnarendran for asking, and dave785 for answering! (Kudos given, of course.)
Manager
Joined: 26 May 2013
Posts: 66
Followers: 0

Kudos [?]: 31 [0], given: 243

Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

21 Jul 2014, 06:47
Surprised no one approached option route. Obviously the solution has to greater than 50% of the total (those who went above yesterday). And only option- D can be 20% greater than Total-Ans.
Manager
Joined: 07 Apr 2014
Posts: 147
Followers: 1

Kudos [?]: 23 [0], given: 81

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

11 Sep 2014, 02:43
conty911 wrote:
Yesterday's closing prices of 2,420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent greater than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

(A) 484
(B) 726
(C) 1,100
(D) 1,320
(E) 1,694

[Reveal] Spoiler:
Source :OG-13; Q71(PS)

Folks, please write the answer with all the steps. The answer is clear cut but the only thing I'm interested in is the interpretation of the word problem and the respective approach to solve it. Thanks.
If any body used tabular approach, i will be glad to see it because i had trouble solving this problem with the same.

convoluted thing...

let x part be higher price
2420-x be the lower price.

now x is 20% greater than 2420-x

x= (2420-x) +0.2(2420-x)
x= 2904-1.2x
2.2x=2904
x=1320

D
Intern
Joined: 03 Oct 2014
Posts: 6
Location: United Kingdom
WE: Engineering (Energy and Utilities)
Followers: 0

Kudos [?]: 6 [0], given: 15

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

09 Oct 2014, 03:11
Math Expert
Joined: 02 Sep 2009
Posts: 36548
Followers: 7077

Kudos [?]: 93108 [0], given: 10552

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

09 Oct 2014, 04:33

$$2.2x = 2,420$$;

$$\frac{11}{5}x=2,420$$;

$$x= \frac{2,420*5}{11}=220*5=1,100$$.
_________________
Intern
Joined: 03 Oct 2014
Posts: 6
Location: United Kingdom
WE: Engineering (Energy and Utilities)
Followers: 0

Kudos [?]: 6 [0], given: 15

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

09 Oct 2014, 04:52
Thanks Bunuel, that makes sense of course, but still leads me to ask, how do you managed to do 2420/11 in your head?
Math Expert
Joined: 02 Sep 2009
Posts: 36548
Followers: 7077

Kudos [?]: 93108 [2] , given: 10552

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]

### Show Tags

09 Oct 2014, 04:56
2
KUDOS
Expert's post
Thanks Bunuel, that makes sense of course, but still leads me to ask, how do you managed to do 2420/11 in your head?

Sometimes you have to do actual math...
_________________
Re: Yesterday's closing prices of 2,420 different stocks listed   [#permalink] 09 Oct 2014, 04:56

Go to page    1   2    Next  [ 39 posts ]

Similar topics Replies Last post
Similar
Topics:
Closing prices for a certain stock were recorded each day for a week 2 16 Aug 2016, 05:10
At the opening of a trading day at a certain stock exchange, the price 4 25 May 2016, 00:56
When the stock market opened yesterday, the price of a share 2 31 Mar 2012, 20:16
61 A certain portfolio consisted of 5 stocks, priced at \$20, 20 19 Jul 2008, 23:15
6 Last year the price per share of Stock X increased by k 5 07 Dec 2007, 17:39
Display posts from previous: Sort by