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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

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:

Each of the products produced yesterday was checked by x or [#permalink]

Show Tags

15 May 2013, 00:31

2

This post received KUDOS

3

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

25% (medium)

Question Stats:

74% (02:50) correct
26% (03:12) wrong based on 152 sessions

HideShow timer Statistics

Each of the products produced yesterday was checked by x or y. 0.5% of the products checked by x are defective and 0.8% of the products checked by y are defective. If the total defective rate of all the products checked by x and y is 0.75%, what fraction of the products was checked by y?

Each of the products produced yesterday was checked by x or y. 0.5% of the products checked by x are defective and 0.8% of the products checked by y are defective. If the total defective rate of all the products checked by x and y is 0.75%, what fraction of the products was checked by y?

A. 3/5 B. 5/6 C. 7/11 D. 4/5 E. 5/8

The easiest way to do these types of questions is to look at the difference between x and y on a number line. x is at 0.5 and y is at 0.8, and together the average is 0.75. This means that every product checked by x brings down the average by 0.25 and every product checked by y brings up the average by 0.05. To balance these two out, y needs to check 5 products for every time x checks 1 product. Hence 1/6 of total checked by x and 5/6 of total checked by y.

Algebra works too but the number line strategy gets you the correct answer quickly. If you practice doing that, this is a 1-minute question, from starting to read to clicking "next".

Re: Each of the products produced yesterday was checked by x or [#permalink]

Show Tags

15 May 2013, 02:59

2

This post received KUDOS

navigator123 wrote:

Each of the products produced yesterday was checked by x or y. 0.5% of the products checked by x are defective and 0.8% of the products checked by y are defective. If the total defective rate of all the products checked by x and y is 0.75%, what fraction of the products was checked by y?

A. 3/5 B. 5/6 C. 7/11 D. 4/5 E. 5/8

This is a allegation problem.

We can use a shortcut.

See the attachment for the shortcut.Its a simple one

So X/Y = 0.05/0.25 = 1/5

Therefore the fraction of products checked by Y = 5/6

Attachments

File comment: The shortcut

untitled.JPG [ 4.43 KiB | Viewed 2010 times ]

_________________

"Kudos" will help me a lot!!!!!!Please donate some!!!

Completed Official Quant Review OG - Quant

In Progress Official Verbal Review OG 13th ed MGMAT IR AWA Structure

Yet to do 100 700+ SC questions MR Verbal MR Quant

Re: Each of the products produced yesterday was checked by x or [#permalink]

Show Tags

28 Jul 2014, 02:38

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.
_________________

Re: Each of the products produced yesterday was checked by x or [#permalink]

Show Tags

09 Aug 2014, 01:54

SrinathVangala wrote:

navigator123 wrote:

Each of the products produced yesterday was checked by x or y. 0.5% of the products checked by x are defective and 0.8% of the products checked by y are defective. If the total defective rate of all the products checked by x and y is 0.75%, what fraction of the products was checked by y?

A. 3/5 B. 5/6 C. 7/11 D. 4/5 E. 5/8

This is a allegation problem.

We can use a shortcut.

See the attachment for the shortcut.Its a simple one

So X/Y = 0.05/0.25 = 1/5

Therefore the fraction of products checked by Y = 5/6

Hi, I am not aware of allegation. can you please explain about this or point me to some useful but short source.

Re: Each of the products produced yesterday was checked by x or [#permalink]

Show Tags

16 Dec 2015, 01:11

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.
_________________

After days of waiting, sharing the tension with other applicants in forums, coming up with different theories about invites patterns, and, overall, refreshing my inbox every five minutes to...

I was totally freaking out. Apparently, most of the HBS invites were already sent and I didn’t get one. However, there are still some to come out on...

In early 2012, when I was working as a biomedical researcher at the National Institutes of Health , I decided that I wanted to get an MBA and make the...