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:

Yesterday's closing prices of 2,420 different stocks listed [#permalink]
14 Sep 2012, 21:18

1

This post received KUDOS

00:00

A

B

C

D

E

Difficulty:

35% (medium)

Question Stats:

64% (02:36) correct
35% (02:02) wrong based on 189 sessions

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?

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.

Re: Yesterday's closing prices of 2420different stocks listed on [#permalink]
14 Sep 2012, 22:36

1

This post received KUDOS

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. D is my answer.

Questions, Pls let me know. Cheers!
_________________

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

Re: Yesterday's closing prices of 2420different stocks listed on [#permalink]
15 Sep 2012, 00:18

6

This post received KUDOS

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

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]
15 Sep 2012, 01:37

5

This post received KUDOS

Expert's post

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.

Answer: D.

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.

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

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]
04 May 2013, 14:15

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...

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]
04 May 2013, 14:43

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...

Can someone please clarify...

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.

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]
04 May 2013, 15:03

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...

Can someone please clarify...

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...

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]
04 May 2013, 16:42

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...

Can someone please clarify...

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.

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]
12 Nov 2013, 10:01

2

This post received 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.

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

Re: Yesterday's closing prices of 2,420 different stocks listed [#permalink]
22 Feb 2014, 02:31

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