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 350,000 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:

A certain research group plans to create computer models of [#permalink]
09 Sep 2013, 09:59

1

This post received KUDOS

6

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

75% (hard)

Question Stats:

50% (02:32) correct
50% (01:42) wrong based on 252 sessions

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

A. x*x – 5x B. (x)(105 – x) C. (100)(105 – x) D. (100)(95 – x) E. (x-5)/100

Re: A certain research group plans to create computer models of [#permalink]
09 Sep 2013, 12:35

1

This post received KUDOS

1

This post was BOOKMARKED

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

a) x*x – 5x b) (x)(105 – x) c) (100)(105 – x) d) (100)(95 – x) e) (x-5)/100

Initial: (x/100)*10000 = 100x (bacterial species) After reduce BY (x - 5)%, the percentage of bacterial species = 1 - (x - 5)% = 1 - (x - 5)/100 = (105 - x)/100 Note: Difference between "reduce to" [means: the remain] and "reduce by" [means: the remain = 1 - "reduce by"] So, the number of bacterial species after reducing: 100x*(105 - x)/100 = (x)*(105 - x) Ans is B.

Re: A certain research group plans to create computer models of [#permalink]
09 Sep 2013, 16:20

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

a) x*x – 5x b) (x)(105 – x) c) (100)(105 – x) d) (100)(95 – x) e) (x-5)/100

I believe the OA may be wrong. I got:

x% of 10000 is: \(\frac{x}{100}(10,000) = 100x\)

The reduced percentage can be stated as follows: \((1 - \frac{x-5}{100})\) \(=\) \((\frac{105-x}{100})\)

Multiplying the selection by the reduced percentage: \(100x\) \((\frac{105-x}{100})\) \(=\) \(x(105-x)\)

B _________________

If my post has contributed to your learning or teaching in any way, feel free to hit the kudos button ^_^

Re: A certain research group plans to create computer models of [#permalink]
09 Sep 2013, 17:38

I think OA is wrong too, but i got D.

out of 10,000 samples, 10,000(x-5)% will be studied. If x was originally 50%, that means 5,000 would have been studied. now at 50%-5%, 4,500 will be studied.

Re: A certain research group plans to create computer models of [#permalink]
11 Oct 2013, 01:37

2

This post received KUDOS

Expert's post

1

This post was BOOKMARKED

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

a) x*x – 5x b) (x)(105 – x) c) (100)(105 – x) d) (100)(95 – x) e) (x-5)/100

The number of species that the group plans to model = \(10,000*\frac{x}{100} = 100x\).

After a budget cut, the group finds it must reduce this selection by (x − 5)%, thus the group will be able to model \(100x*(1-\frac{x-5}{100})=x(105-x)\).

Re: A certain research group plans to create computer models of [#permalink]
11 Oct 2013, 04:15

Bunuel wrote:

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

a) x*x – 5x b) (x)(105 – x) c) (100)(105 – x) d) (100)(95 – x) e) (x-5)/100

The number of species that the group plans to model = \(10,000*\frac{x}{100} = 100x\).

After a budget cut, the group finds it must reduce this selection by (x − 5)%, thus the group will be able to model \(100x*(1-\frac{x-5}{100})=x(105-x)\).

Re: A certain research group plans to create computer models of [#permalink]
10 Jan 2014, 06:14

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

a) x*x – 5x b) (x)(105 – x) c) (100)(105 – x) d) (100)(95 – x) e) (x-5)/100

Use smart numbers.

OK lets say x = 50

So then 50% of 10,000 = 5000 Now after budget cut = 5000*45/100 = (50)(45)

Re: A certain research group plans to create computer models of [#permalink]
20 Jul 2014, 04:43

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

A. \(\frac{x-5}{100}\) B. x^2 – 5x C. (x)(105 – x) D. (100)(105 – x) E. (100)(95 – x) _________________

“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

Re: A certain research group plans to create computer models of [#permalink]
20 Jul 2014, 04:46

1

This post received KUDOS

Expert's post

WoundedTiger wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

A. \(\frac{x-5}{100}\) B. x^2 – 5x C. (x)(105 – x) D. (100)(105 – x) E. (100)(95 – x)

Merging topics.

Please refer to the discussion above. _________________

Re: A certain research group plans to create computer models of [#permalink]
22 Jul 2014, 12:13

Bunuel wrote:

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

a) x*x – 5x b) (x)(105 – x) c) (100)(105 – x) d) (100)(95 – x) e) (x-5)/100

The number of species that the group plans to model = \(10,000*\frac{x}{100} = 100x\).

After a budget cut, the group finds it must reduce this selection by (x − 5)%, thus the group will be able to model \(100x*(1-\frac{x-5}{100})=x(105-x)\).

Answer: B.

Hope it's clear.

Hi why you wrote 1- (x-5)% in the last step? could not understand the step.

Re: A certain research group plans to create computer models of [#permalink]
22 Jul 2014, 22:57

GGMAT760 wrote:

Bunuel wrote:

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

a) x*x – 5x b) (x)(105 – x) c) (100)(105 – x) d) (100)(95 – x) e) (x-5)/100

The number of species that the group plans to model = \(10,000*\frac{x}{100} = 100x\).

After a budget cut, the group finds it must reduce this selection by (x − 5)%, thus the group will be able to model \(100x*(1-\frac{x-5}{100})=x(105-x)\).

Answer: B.

Hope it's clear.

Hi why you wrote 1- (x-5)% in the last step? could not understand the step.

Thanks in advance

Actually its a reduction of (x-5)%; so written in that way

A certain research group plans to create computer models of [#permalink]
10 Aug 2014, 18:22

Based on the answer choices and the question, this question begs the use of x=5 as a sample number. Initial = 5%*10000 = 500 Reduction = 5-5=0%, so no math required here to calculate the reduction; just make sure that you can calculate 500 in your answer.

A. x*x – 5x = 0; No B. (x)(105 – x) = 500; Winner! C. (100)(105 – x) > 500; No D. (100)(95 – x) > 500; No E. (x-5)/100 = 0; No

B

I was a strong believer in using algebra for percent problems, but after missing 95% of them because of some careless error, I was converted to the sample number method. Generally speaking, picking smart numbers for percent problems will get you the correct answer more quickly and with the least errors.

Re: A certain research group plans to create computer models of [#permalink]
20 Mar 2015, 22:19

suyash23n wrote:

A certain research group plans to create computer models of x% of a list of 10,000 bacterial species known to inhabit the human body. After a budget cut, the group finds it must reduce this selection by (x − 5)%. In terms of x, how many species of bacteria will the group be able to model?

A. x*x – 5x B. (x)(105 – x) C. (100)(105 – x) D. (100)(95 – x) E. (x-5)/100

Type of Visa: You will be applying for a Non-Immigrant F-1 (Student) US Visa. Applying for a Visa: Create an account on: https://cgifederal.secure.force.com/?language=Englishcountry=India Complete...

I started running back in 2005. I finally conquered what seemed impossible. Not sure when I would be able to do full marathon, but this will do for now...