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:

If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066% (B) 0.066% (C) 0.66% (D) 6.6% (E) 66%

Problem Solving Question: 10 Category:Arithmetic Percents Page: 63 Difficulty: 550

Each week we'll be posting several questions from The Official Guide For GMAT® Quantitative Review, 2ND Edition and then after couple of days we'll provide Official Answer (OA) to them along with a slution.

We'll be glad if you participate in development of this project: 1. Please provide your solutions to the questions; 2. Please vote for the best solutions by pressing Kudos button; 3. Please vote for the questions themselves by pressing Kudos button; 4. Please share your views on difficulty level of the questions, so that we have most precise evaluation.

If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066% (B) 0.066% (C) 0.66% (D) 6.6% (E) 66%

We need to find 664,579 is what percent of 10 million: \(\frac{664,579}{10,000,000}*100\approx{6.6%}\).

Re: If there are 664,579 prime numbers among the first 10 millio [#permalink]

Show Tags

30 Dec 2013, 04:14

If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066% (B) 0.066% (C) 0.66% (D) 6.6% (E) 66%

Sol: Given there 664 579 prime nos in first 10 million positive integers.So % will be

(0.664579*10^6/10 *10^6)*100 ------> 0.664579*10 and thus 6.6% Ans D
_________________

“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: If there are 664,579 prime numbers among the first 10 millio [#permalink]

Show Tags

31 Mar 2015, 05:56

664,579 / 10,000,000 *100 =x%

you can reduce the 10 million by 100, so that you only have 100,000 in the denominator. Now, bot the nominator and denominator have the same amount of digits and from this point you can ask yourself how much for e.g. 664/100 is. The solution is 6,64 or in this case 6,6%

If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066% (B) 0.066% (C) 0.66% (D) 6.6% (E) 66%

Problem Solving Question: 10 Category:Arithmetic Percents Page: 63 Difficulty: 550

Each week we'll be posting several questions from The Official Guide For GMAT® Quantitative Review, 2ND Edition and then after couple of days we'll provide Official Answer (OA) to them along with a slution.

We'll be glad if you participate in development of this project: 1. Please provide your solutions to the questions; 2. Please vote for the best solutions by pressing Kudos button; 3. Please vote for the questions themselves by pressing Kudos button; 4. Please share your views on difficulty level of the questions, so that we have most precise evaluation.

-- Optimus Prep's GMAT On Demand course for only $299 covers all verbal and quant. concepts in detail. Visit the following link to get your 7 days free trial account: http://www.optimus-prep.com/gmat-on-demand-course

Re: If there are 664,579 prime numbers among the first 10 millio [#permalink]

Show Tags

11 Nov 2015, 13:11

You can find interesting facts and puzzles about Prime Numbers and Magic Squares, Smith Numbers, and Arithmetic and Palindromic Primes on Glenn Westmore's blog.

Re: If there are 664,579 prime numbers among the first 10 millio [#permalink]

Show Tags

12 Nov 2017, 22:20

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.
_________________