GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 14 Dec 2018, 09:07

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
Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • Typical Day of a UCLA MBA Student - Recording of Webinar with UCLA Adcom and Student

     December 14, 2018

     December 14, 2018

     10:00 PM PST

     11:00 PM PST

    Carolyn and Brett - nicely explained what is the typical day of a UCLA student. I am posting below recording of the webinar for those who could't attend this session.
  • Free GMAT Strategy Webinar

     December 15, 2018

     December 15, 2018

     07:00 AM PST

     09:00 AM PST

    Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

A chess player won 25 percent of the first 20 games

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Manager
Manager
avatar
Joined: 02 Sep 2012
Posts: 203
Location: United States
Concentration: Entrepreneurship, Finance
GMAT Date: 07-25-2013
GPA: 3.83
WE: Architecture (Computer Hardware)
A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 10 May 2013, 23:48
2
17
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

64% (01:10) correct 36% (00:49) wrong based on 292 sessions

HideShow timer Statistics

A chess player won 25 percent of the first 20 games he played and all of his remaining games. What is the ratio of the number of games he won to the number of the games he lost?

(1) If the player had won 25 percent of the total games he played, he would have lost 30 more games than he actually did.

(2) The player won 75 percent of the games he played.
Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51215
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 11 May 2013, 02:35
4
7
skamal7 wrote:
A chess player won 25 percent of the first 20 games he played and all of his remaining games. What is the ratio of the number of games he won to the number of the games he lost?

(1) If the player had won 25 percent of the total games he played, he would have lost 30 more games than he actually did.

(2) The player won 75 percent of the games he played.


A chess player won 25 percent of the first 20 games he played and all of his remaining games. What is the ratio of the number of games he won to the number of the games he lost?

(1) If the player had won 25 percent of the total games he played, he would have lost 30 more games than he actually did. The player won 25% of his first 20 games and 100% of the remaining games, in order to win 25% of total matches he should have won 25% of the remaining games (instead of 100%, so 75% less). So 75% losses in the remaining games result in 30 more losses: 0.75*R=30, where R is # of the remaining games. We have only one unknown R, hence we can solve for it and thus we'll have all information needed to get the ratio. Sufficient.

(2) The player won 75 percent of the games he played --> 0.25*20+1*R=0.75*(20+R). The same here: we have only one unknown R, hence we can solve for it and thus we'll have all information needed to get the ratio. Sufficient.

Answer: D.

Similar questions to practice:
after-winning-80-of-his-first-40-matches-igby-won-129062.html
after-winning-50-percent-of-the-first-30-matches-she-played-129132.html
after-winning-80-percent-of-the-fi-rst-40-games-it-played-129338.html
after-winning-50-percent-of-the-first-x-games-it-played-149675.html

Hope it helps.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

General Discussion
VP
VP
User avatar
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1063
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
GMAT ToolKit User
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 10 May 2013, 23:59
3
1
A chess player won 25 percent of the first 20 games he played and all of his remaining games. What is the ratio of the number of games he won to the number of the games he lost?

In the first 20 games, 5 W and 15 L. Overall he won \(5+R\) games and lost \(15\). We need to find R

(1) If the player had won 25 percent of the total games he played, he would have lost 30 more games than he actually did.
"If the player had won 25 percent of the total games he played" = lost 75%
\((20+R)*75%=30+15\) the first part is the total losses, the second part is the is 30 more games than he actually did lose (15)

\(0.75R=30\)

\(R=40\)
Suffcient

(2) The player won 75 percent of the games he played.
\(5+R=75%(20+R)\) the first part is the number of games he won, the second part is the transaltion of "won 75 percent of the games he played"

\(R=40\)
Sufficient
D
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Manager
Manager
avatar
Joined: 02 Sep 2012
Posts: 203
Location: United States
Concentration: Entrepreneurship, Finance
GMAT Date: 07-25-2013
GPA: 3.83
WE: Architecture (Computer Hardware)
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 11 May 2013, 00:07
1
I am really struggling wit these type of word problems.Any stratergy how to improve? I am not able to translate these words into algebric equations

bunnel/zarollu any similar questions to practice in this forum?
VP
VP
User avatar
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1063
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
GMAT ToolKit User
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 11 May 2013, 00:18
1
skamal7 wrote:
I am really struggling wit these type of word problems.Any stratergy how to improve? I am not able to translate these words into algebric equations

bunnel/zarollu any similar questions to practice in this forum?


You can refer here
gmat-ps-question-directory-by-topic-difficulty-127957.html
ds-question-directory-by-topic-difficulty-128728.html
look for the "word" problems

Hope this helps
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Manager
Manager
User avatar
Status: *Lost and found*
Joined: 25 Feb 2013
Posts: 121
Location: India
Concentration: General Management, Technology
GMAT 1: 640 Q42 V37
GPA: 3.5
WE: Web Development (Computer Software)
GMAT ToolKit User
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 11 May 2013, 00:26
1
1
skamal7 wrote:
A chess player won 25 percent of the first 20 games he played and all of his remaining games. What is the ratio of the number of games he won to the number of the games he lost?
(1) If the player had won 25 percent of the total games he played, he would have lost 30 more games than he actually did.
(2) The player won 75 percent of the games he played.


I approached the problem in this way,
Let x be the number of games played after the first 20 games. Now we already know, that out of the 20 games, 5 were won by the player and 15 lost.

Also, that since he doesnt loose any more games, the total number of losses remain to be 15.
But the games won can be assumed as 5 + x
Hence the desired ratio is 5+x:15

To calculate value of x we use the given statements:
Stamement 1. if the player had won 25% of the total games i.e. games lost = 75/100(20 + x) = 15 + 3/4x.
=> 15+3/4x -15 = 30
=> 3/4x = 30
=> x = 4/3 * 30 = 40.
Hence the ratio can be found as 45:15.

For Statement 2. If the player had won 75 of total games i.e. 5+x/20+x = 75/100 => x = 40
Hence the ratio is again found to be 45:15

The answer for me would be [D]**edited..typo! , both the statments are individually sufficient.

Regards,
Arpan
_________________

Feed me some KUDOS! :) :) *always hungry*

My Thread : Recommendation Letters

Manager
Manager
avatar
Joined: 02 Sep 2012
Posts: 203
Location: United States
Concentration: Entrepreneurship, Finance
GMAT Date: 07-25-2013
GPA: 3.83
WE: Architecture (Computer Hardware)
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 11 May 2013, 02:39
Bunnel,
I have a query.
If the player had won 25 percent of the total games he played" = lost 75%----- why do we want to convert into the opposite of how much % lost..can we get the answer without converting this?
Manager
Manager
User avatar
Status: *Lost and found*
Joined: 25 Feb 2013
Posts: 121
Location: India
Concentration: General Management, Technology
GMAT 1: 640 Q42 V37
GPA: 3.5
WE: Web Development (Computer Software)
GMAT ToolKit User
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 11 May 2013, 20:21
1
skamal7 wrote:
Bunnel,
I have a query.
If the player had won 25 percent of the total games he played" = lost 75%----- why do we want to convert into the opposite of how much % lost..can we get the answer without converting this?


Since the RHS in the statement 1 is 30 i.e. "the player would have lost 30 more games than he actually did", which is the number of games lost, its important to frame the equation in terms of number of games lost by the player. Statement 1 in general does not speak about the exact number of wins, but then again we can derive the answer from the wins as well.

Let x be the number of games played after the first 20 games. Now we already know, that out of the 20 games, 5 were won by the player and 15 lost.
The total number of games won can be assumed as 5 + x and the losses as of now are 15. Total games played is 20 + x.
If the player had won 25% of the total games i.e. 25/100 * (20 + x) games won.
Now as mentioned, the player would loose 30 more games. Hence the number of wins would reduce by 30 i.e. 5 + x -30 is the total number of wins.
Equating the same,
25/100*(20 + x) = 5 + x - 30
=>5 + x/4 = x - 25
=> x = 40

The above values are concurrent with our other findings. Although this procedure does provide the answer, but would not be the best of the methods to use given the question. Please correct me if I am wrong Bunnel! Im sorry I went ahead over this even though the query was directed at you :)

Regards,
Arpan
_________________

Feed me some KUDOS! :) :) *always hungry*

My Thread : Recommendation Letters

Veritas Prep GMAT Instructor
User avatar
P
Joined: 16 Oct 2010
Posts: 8678
Location: Pune, India
Re: A chess player won 25 percent of the first 20 games  [#permalink]

Show Tags

New post 02 Dec 2018, 23:20
skamal7 wrote:
A chess player won 25 percent of the first 20 games he played and all of his remaining games. What is the ratio of the number of games he won to the number of the games he lost?

(1) If the player had won 25 percent of the total games he played, he would have lost 30 more games than he actually did.

(2) The player won 75 percent of the games he played.


He won 25% of 20 games and 100% of the rest.

(1) If the player had won 25 percent of the total games he played, he would have lost 30 more games than he actually did.

If he had won 25% of the total games, he would have won 25% of the remaining games too and lost 75% of the remaining games. This 75% of remaining games = 30 so number of remaining games = 30*4/3 = 40
He won 25% of 20 i.e. 5 and all 40 of the others so he won 45 games and lost 15 games. The required ratio = 3:1
Sufficient.

(2) The player won 75 percent of the games he played.

Use weighted averages to solve this:
Aavg = 75%
w1/w2 = (A2 - Aavg)/(Aavg - A1) = (100 - 75)/(75 - 25) = 1/2
So since 20 games were played first, the rest of the games were twice in number i.e. 40. He won 25% of 20 i.e. 5 and all 40 of the others so he won 45 games and lost 15 games. The required ratio = 3:1
Sufficient.

Answer (D)
_________________

Karishma
Veritas Prep GMAT Instructor

Learn more about how Veritas Prep can help you achieve a great GMAT score by checking out their GMAT Prep Options >

GMAT Club Bot
Re: A chess player won 25 percent of the first 20 games &nbs [#permalink] 02 Dec 2018, 23:20
Display posts from previous: Sort by

A chess player won 25 percent of the first 20 games

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.