A paint store makes peach paint according to the formula ab

Expert replies

gmatter2012: Master | Next Rank: 500 Posts; Posts: 138; Joined: Sat May 05, 2012 7:03 pm; Thanked: 1 times

by gmatter2012 » Mon Jul 09, 2012 10:50 am

formula

white : 3/5 gallon
red : 1/4 gallon
yellow :1/3 gallon

A paint store makes peach paint according to the formula above. The numbers of gallons of white and yellow paint used in a batch of peach paint are always each an integer. If the store owner wants to make the smallest batch of peach paint possible, how many gallons of red are needed?

A) 1/4
(B) 1
(C) 3(3/4)
(D) 5
(E) 9

Like this post

Source: Beat The GMAT — Problem Solving | Mon Jul 09, 2012 10:50 am

GMAT/MBA Expert

Anurag@Gurome: GMAT Instructor; Posts: 3835; Joined: Fri Apr 02, 2010 10:00 pmFollowed by: 523 members; Location: Milpitas, CA; Thanked: 1854 times; GMAT Score:770

by Anurag@Gurome » Mon Jul 09, 2012 10:58 am

W:R:Y = (3/5):(1/4):(1/3)

To make the ratio of white and yellow an integer, we need to multiply each term in the ratio by a multiple of 3 and 5. And as we need to make the smallest batch possible, we will multiply by the LCM of 3 and 5 = 15

Hence, W:R:Y = 9:(15/4):5

Hence, 15/4 = 3 and 3/4 gallons of red paint is required.

The correct answer is C.

Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/

Like this post

alex.gellatly: Master | Next Rank: 500 Posts; Posts: 435; Joined: Wed Nov 16, 2011 7:27 amFollowed by: 16 members; Thanked: 48 times

by alex.gellatly » Mon Jul 09, 2012 10:06 pm

gmatter2012 wrote:formula

white : 3/5 gallon
red : 1/4 gallon
yellow :1/3 gallon

A paint store makes peach paint according to the formula above. The numbers of gallons of white and yellow paint used in a batch of peach paint are always each an integer. If the store owner wants to make the smallest batch of peach paint possible, how many gallons of red are needed?

A) 1/4
(B) 1
(C) 3(3/4)
(D) 5
(E) 9

To make White and Yellow both integers the total amount of paint (in gallons) must be a multiple of 5 and 3. The least amount of paint used is thus 3*5=15 gallons. So White is (3/5)*15 = 9, Red is (1/4)*15 = 15/4 or 3 and 3/4, and Yellow is (1/3)*15 = 5. So answer should be C.

Like this post

gmatter2012: Master | Next Rank: 500 Posts; Posts: 138; Joined: Sat May 05, 2012 7:03 pm; Thanked: 1 times

by gmatter2012 » Tue Jul 10, 2012 2:28 am

Now this has become very clear, this question was solved in a very peculiar way , in its source .

but after seeing the explanation here, its clear

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

559 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review