Find all School-related info fast with the new School-Specific MBA Forum

It is currently 25 Oct 2014, 20:09

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Ratio and Proportion

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 19 May 2012
Posts: 1
Followers: 0

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

Ratio and Proportion [#permalink] New post 16 Jul 2012, 08:23
Hi Guys,

Need help in understanding a simple concept in Ratio & Proportion. Here it goes:

If a:b = 2/3 ; b:c=3/4 ; c:d=8/9 and d:e = 27/12, then what is the ratio of a:b:c:d:e ??

Thanks a lot.

Cheers
BSchool Thread Master
User avatar
Status: Tutor
Joined: 05 Apr 2011
Posts: 431
Location: India
Concentration: Finance, Marketing
Schools: XLRI (A)
GMAT 1: 570 Q49 V19
GMAT 2: 700 Q51 V31
GPA: 3
WE: Information Technology (Computer Software)
Followers: 58

Kudos [?]: 255 [0], given: 44

Premium Member
Re: Ratio and Proportion [#permalink] New post 16 Jul 2012, 09:52
Hi,


a:b = 2/3 ; b:c=3/4 ; c:d=8/9 and d:e = 27/12

take d:e = 27/12 => d= 27*e/12 = 9e/4 ...(1)

c:d = 8/9 => c = 8*d/9 = 8 *(9e/4)/9 (substituting value of d from (1) )
=> c = 2e ....(2)

b:c = 3/4 => b =3c/4 => 3*2e/4 (substituting value of c from (2) )

=> b = 3e/2 ....(3)

a/b = 2/3 => a=2b/3 => a = 2(3e/2) / 3 (substituting value of b from (3) )

=> a = e ....(4)

From (1) , (2) , (3) and (4) we have

a:b:c:d:e = e:(3e/2):2e:(9e/4):e = 1:3/2:2:9/4:1 = 4:6:8:9:4

hope this helps!
_________________

ankit
you must believe

How to start GMAT preparations?
How to Improve Quant Score?
gmatclub topic tags
Check out my GMAT debrief
Thursdays with Ron link
Looking for a Quant tutor? Check out my post for the same!

Combined Formula Sheet :
Number Properties || Word Problems and PnC || Equations, Inequalities || Geometry

How to Solve :
Statistics || Reflection of a line || Remainder Problems

Senior Manager
Senior Manager
User avatar
Joined: 28 Apr 2012
Posts: 310
Location: India
GMAT 1: 650 Q48 V31
GMAT 2: 770 Q50 V47
WE: Information Technology (Computer Software)
Followers: 13

Kudos [?]: 199 [0], given: 142

Re: Ratio and Proportion [#permalink] New post 16 Jul 2012, 10:44
gmat102012 wrote:
Hi Guys,

Need help in understanding a simple concept in Ratio & Proportion. Here it goes:

If a:b = 2/3 ; b:c=3/4 ; c:d=8/9 and d:e = 27/12, then what is the ratio of a:b:c:d:e ??

Thanks a lot.

Cheers


Simplify the fractions and start with the largest:

d/e=27/12 = 9/4
Now your task is to make alternate numerator and denominator same, so that they cancel out on multiplication.


so we already have
1. d/e =9/4
2. c/d=8/9
3. b/c=3/4=6/8
4. a/b=2/3=4/6

Mark - this has made the value of my variables same in all the ratios:
a=4 (from 4)
b=6 (from 4 and 3)
c=8 (from 3 and 2)
d=9 (from 2 and 1)
e=4 (from 1)
=> a:b:c:d:e = 4:6:8:9:4

Alternatively, quick way to find is:

a/e = (a/b) x (b/c) x (c/d) x (d/e) X (e/e)
= (2/3) X (3/4) x (8/9) x (27/12) X (1/1)
= (12/18) x (18/24) x (24/27) x (27/12) x (12/12) -> starting from the biggest make the adjacent non-paired numbers ( not within braces) equal, while maintaining the ratio
Take the numerators
12:18:24:27:12
Cancel common factors
4:6:8:9:4
_________________

"Appreciation is a wonderful thing. It makes what is excellent in others belong to us as well."
― Voltaire


Press Kudos, if I have helped.
Thanks!

shit-happens-my-journey-to-172475.html#p1372807

Expert Post
1 KUDOS received
Veritas Prep GMAT Instructor
User avatar
Joined: 16 Oct 2010
Posts: 4877
Location: Pune, India
Followers: 1157

Kudos [?]: 5383 [1] , given: 165

Re: Ratio and Proportion [#permalink] New post 17 Jul 2012, 21:26
1
This post received
KUDOS
Expert's post
gmat102012 wrote:
Hi Guys,

Need help in understanding a simple concept in Ratio & Proportion. Here it goes:

If a:b = 2/3 ; b:c=3/4 ; c:d=8/9 and d:e = 27/12, then what is the ratio of a:b:c:d:e ??

Thanks a lot.

Cheers


Given:
a:b = 2:3 and b:c = 3:4
What does the ratio a:b = 2:3 imply? It means "if a is 2, b is 3"
What does the ratio b:c = 3:4 imply? It means "if b is 3, c is 4"

What do we get from this? "if a is 2, b is 3 and c is 4"
If a:b:c = 2:3:4 and c:d = 8:9
c is not the same in both the ratios but can we make it same? Multiply the first ratio by 2. (ratio doesn't change if you multiply/divide each term by the same number)
a:b:c = 4:6:8 and c:d = 8:9
So, a:b:c:d = 4:6:8:9 and d:e = 27:12 = 9:4 (we divide the ratio by 3. It still stays the same.)
So a:b:c:d:e = 4:6:8:9:4

For more on ratios, check: http://www.veritasprep.com/blog/2011/03 ... of-ratios/
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Save $100 on Veritas Prep GMAT Courses And Admissions Consulting
Enroll now. Pay later. Take advantage of Veritas Prep's flexible payment plan options.

Veritas Prep Reviews

CEO
CEO
User avatar
Joined: 09 Sep 2013
Posts: 2871
Followers: 208

Kudos [?]: 43 [0], given: 0

Premium Member
Re: Ratio and Proportion [#permalink] New post 04 Dec 2013, 11:56
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Re: Ratio and Proportion   [#permalink] 04 Dec 2013, 11:56
    Similar topics Author Replies Last post
Similar
Topics:
Ratio and Proportion soaringAlone 1 15 Jun 2011, 21:29
1 Ratio and Proportion ChenggongMAS 5 04 Jan 2011, 21:00
Experts publish their posts in the topic Ratio & Proportion........ pzazz12 2 19 Oct 2010, 04:36
At a certain theater, the cost of each adult's ticket is $5 prashi82 6 21 Aug 2008, 20:21
Better books for ratio and proportion pansarda 0 07 Jan 2008, 10:06
Display posts from previous: Sort by

Ratio and Proportion

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

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

Powered by phpBB © phpBB Group and phpBB SEO

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®.