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

It is currently 18 Dec 2018, 13:28

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
  • Happy Christmas 20% Sale! Math Revolution All-In-One Products!

     December 20, 2018

     December 20, 2018

     10:00 PM PST

     11:00 PM PST

    This is the most inexpensive and attractive price in the market. Get the course now!
  • Key Strategies to Master GMAT SC

     December 22, 2018

     December 22, 2018

     07:00 AM PST

     09:00 AM PST

    Attend this webinar to learn how to leverage Meaning and Logic to solve the most challenging Sentence Correction Questions.

There are 2 candles with the same height. It takes t mins for A to bur

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

Hide Tags

Senior SC Moderator
User avatar
V
Joined: 14 Nov 2016
Posts: 1324
Location: Malaysia
GMAT ToolKit User Premium Member
There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 22 Feb 2017, 17:14
1
19
00:00
A
B
C
D
E

Difficulty:

  95% (hard)

Question Stats:

56% (02:42) correct 44% (02:49) wrong based on 184 sessions

HideShow timer Statistics

There are 2 candles with the same height. It takes t mins for A to burn, and it takes 2t mins for B to burn. When the candles are burnt at the same time, how many minutes did it take for the height of B to be twice the height of A?

A. \(\frac{t}{3}\)      

B. \(\frac{2t}{3}\)

C. \(\frac{t}{2}\)

D. \(\frac{3t}{4}\) 

E. \(\frac{4t}{5}\)

_________________

"Be challenged at EVERY MOMENT."

“Strength doesn’t come from what you can do. It comes from overcoming the things you once thought you couldn’t.”

"Each stage of the journey is crucial to attaining new heights of knowledge."

Rules for posting in verbal forum | Please DO NOT post short answer in your post!

Advanced Search : https://gmatclub.com/forum/advanced-search/

VP
VP
avatar
P
Joined: 07 Dec 2014
Posts: 1130
There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 22 Feb 2017, 19:59
2
2
AustinKL wrote:
There are 2 candles with the same height. It takes t mins for A to burn, and it takes 2t mins for B to burn. When the candles are burnt at the same time, how many minutes did it take for the height of B to be twice the height of A?

A. \(\frac{t}{3}\)      

B. \(\frac{2t}{3}\)

C. \(\frac{t}{2}\)

D. \(\frac{3t}{4}\) 

E. \(\frac{4t}{5}\)


if A burns twice as fast as B,
then 2/3 of A and 1/3 of B will burn in the same time
and the remaining 2/3 of B will be twice the height of the remaining 1/3 of A
fraction of work done by A=2/3
rate of A=1/t
(2/3)/(1/t)=2t/3 minutes
B
Manager
Manager
avatar
D
Joined: 17 May 2015
Posts: 249
Re: There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 04 Jun 2017, 03:58
2
1
hazelnut wrote:
There are 2 candles with the same height. It takes t mins for A to burn, and it takes 2t mins for B to burn. When the candles are burnt at the same time, how many minutes did it take for the height of B to be twice the height of A?

A. \(\frac{t}{3}\)      

B. \(\frac{2t}{3}\)

C. \(\frac{t}{2}\)

D. \(\frac{3t}{4}\) 

E. \(\frac{4t}{5}\)


Hi,

Let the height of two candles is 1. Let the required time is x minutes.

Height of candle A after x minutes = \(1 - \frac{x}{t}\)
And
Height of candle B after x minutes = \(1 - \frac{x}{2t}\)

From the given condition:

\(2*(1 - \frac{x}{t}) = 1 - \frac{x}{2t}\)

=> \(\frac{2x}{t} - \frac{x}{2t} = 1\)

=> \(\frac{4x - x}{2t} = 1\)

=> \(x = \frac{2t}{3}\)

Thanks.
Director
Director
User avatar
P
Joined: 13 Mar 2017
Posts: 678
Location: India
Concentration: General Management, Entrepreneurship
GPA: 3.8
WE: Engineering (Energy and Utilities)
CAT Tests
Re: There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 11 Aug 2017, 02:54
2
2
hazelnut wrote:
There are 2 candles with the same height. It takes t mins for A to burn, and it takes 2t mins for B to burn. When the candles are burnt at the same time, how many minutes did it take for the height of B to be twice the height of A?

A. \(\frac{t}{3}\)      

B. \(\frac{2t}{3}\)

C. \(\frac{t}{2}\)

D. \(\frac{3t}{4}\) 

E. \(\frac{4t}{5}\)



Let h be the height of the candle.
So, A burns at a speed of h/t
B burns at a speed of h/2t

Let the required time be T
so A's height after T min = h - (h/t)*T
B's height after T min = h-(h/2t)*T


h-(h/2t)*T = 2* (h - (h/t)*T)
h = 3/2*(h/t)*T
T = 2/3* t

Answer B

_________________

CAT 2017 99th percentiler : VA 97.27 | DI-LR 96.84 | QA 98.04 | OA 98.95
UPSC Aspirants : Get my app UPSC Important News Reader from Play store.

MBA Social Network : WebMaggu


Appreciate by Clicking +1 Kudos ( Lets be more generous friends.)



What I believe is : "Nothing is Impossible, Even Impossible says I'm Possible" : "Stay Hungry, Stay Foolish".

Senior PS Moderator
User avatar
V
Joined: 26 Feb 2016
Posts: 3327
Location: India
GPA: 3.12
Premium Member CAT Tests
There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 11 Aug 2017, 05:37
Assume t=30 seconds.
Let the height of the candle be 300 unit.
Candle A which burns in 30 seconds, burns at a rate of 10 units/second.
Similarly Candle B which burns in 2t(60) seconds, burns at a rate of 5 units/second

Now evaluating the answer choices,

Option A(\(\frac{t}{3}\)) gives time of burning at 10 seconds
In 10 seconds, Candle A burns 100 units making the height of the candle 200 units.
Candle B burns 50 units, making the height 250 units.
Candle B's height is not equal to twice Candle A's height.

Option B(\(\frac{2t}{3}\)) gives time of burning at 20 seconds
In 10 seconds, Candle A burns 200 units making the height of the candle 100 units.
Candle B burns 100 units, making the height 200 units.

Candle B's height is equal to twice Candle A's height. That is our answer!(Option B)
_________________

You've got what it takes, but it will take everything you've got

Manager
Manager
avatar
B
Joined: 02 Nov 2015
Posts: 165
GMAT 1: 640 Q49 V29
Premium Member
Re: There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 11 Aug 2017, 08:52
shashankism wrote:
hazelnut wrote:
There are 2 candles with the same height. It takes t mins for A to burn, and it takes 2t mins for B to burn. When the candles are burnt at the same time, how many minutes did it take for the height of B to be twice the height of A?

A. \(\frac{t}{3}\)      

B. \(\frac{2t}{3}\)

C. \(\frac{t}{2}\)

D. \(\frac{3t}{4}\) 

E. \(\frac{4t}{5}\)



Let h be the height of the candle.
So, A burns at a speed of h/t
B burns at a speed of h/2t

Let the required time be T
so A's height after T min = h - (h/t)*T
B's height after T min = h-(h/2t)*T


h-(h/2t)*T = 2* (h - (h/t)*T)
h = 3/2*(h/t)*T
T = 2/3* t

Answer B

Very lucid explanation.
Thanks . Very helpful for me..

Sent from my Lenovo TAB S8-50LC using GMAT Club Forum mobile app
Intern
Intern
User avatar
S
Joined: 15 Mar 2017
Posts: 42
Location: India
Concentration: International Business, Strategy
GMAT 1: 720 Q50 V37
GPA: 4
Re: There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 11 Aug 2017, 09:46
1
We can calculate the answer by simply plugging the values
Let's assume the height of each candle is 60cm and time taken to burn candle A is 60sec and time to burn B is 120sec

In 30 secs: A will be of height 30 cm and B will be of the height 45cm. It's still not double. Time taken would be a bit more for the length to double.
IN 40 secs: A will be of height 20 cm and B will be of the height 40cm. Time elapsed to double the height was 40 secs.

Our assumed time "t" was 60 secs. Checking the values, we get: time required=2/3 ( total time)
_________________

You give kudos, you get kudos. :D

Director
Director
User avatar
P
Joined: 13 Mar 2017
Posts: 678
Location: India
Concentration: General Management, Entrepreneurship
GPA: 3.8
WE: Engineering (Energy and Utilities)
CAT Tests
Re: There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 11 Aug 2017, 10:28
kumarparitosh123 wrote:
shashankism wrote:
hazelnut wrote:
There are 2 candles with the same height. It takes t mins for A to burn, and it takes 2t mins for B to burn. When the candles are burnt at the same time, how many minutes did it take for the height of B to be twice the height of A?

A. \(\frac{t}{3}\)      

B. \(\frac{2t}{3}\)

C. \(\frac{t}{2}\)

D. \(\frac{3t}{4}\) 

E. \(\frac{4t}{5}\)



Let h be the height of the candle.
So, A burns at a speed of h/t
B burns at a speed of h/2t

Let the required time be T
so A's height after T min = h - (h/t)*T
B's height after T min = h-(h/2t)*T


h-(h/2t)*T = 2* (h - (h/t)*T)
h = 3/2*(h/t)*T
T = 2/3* t

Answer B

Very lucid explanation.
Thanks . Very helpful for me..

Sent from my Lenovo TAB S8-50LC using GMAT Club Forum mobile app


Thanks kumarparitosh123, I will be coming up with solutions of more problems once I take GMAT. I will target some really good questions. :)
_________________

CAT 2017 99th percentiler : VA 97.27 | DI-LR 96.84 | QA 98.04 | OA 98.95
UPSC Aspirants : Get my app UPSC Important News Reader from Play store.

MBA Social Network : WebMaggu


Appreciate by Clicking +1 Kudos ( Lets be more generous friends.)



What I believe is : "Nothing is Impossible, Even Impossible says I'm Possible" : "Stay Hungry, Stay Foolish".

Senior Manager
Senior Manager
avatar
G
Joined: 02 Apr 2014
Posts: 473
GMAT 1: 700 Q50 V34
Re: There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 19 Feb 2018, 13:01
Let height of candles be, 3L
if candle B, burnt L length(Remaining length - 2L), candle A would have burnt 2L length (remaining length - L).
So when candle B has burnt L length, its height will be twice as that of candle A.
Time taken for full length (3L) candle B to burn = 2t
Time taken for L length of candle B to burn = 2t/3
Intern
Intern
avatar
B
Joined: 09 Nov 2015
Posts: 32
Re: There are 2 candles with the same height. It takes t mins for A to bur  [#permalink]

Show Tags

New post 20 Feb 2018, 23:35
Let the required time be X mins. In 1 min Candles A and B will burn (1/t)th and (1/2t)th of their respective lengths. In X mins, they will burn (X/t)th and (X2t)th of their lengths. So, remaining lengths of A and B will be (1-(X/t)) and (1-(X/2t)) respectively. But after X mins. height of B will be twice that of A. So,
2(1-(X/t))=1-(X/2t). Solving we get X=2t/3. Ans: B
GMAT Club Bot
Re: There are 2 candles with the same height. It takes t mins for A to bur &nbs [#permalink] 20 Feb 2018, 23:35
Display posts from previous: Sort by

There are 2 candles with the same height. It takes t mins for A to bur

  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®.