GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 16 Jan 2019, 16:45

### 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

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

## Events & Promotions

###### Events & Promotions in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
• ### The winning strategy for a high GRE score

January 17, 2019

January 17, 2019

08:00 AM PST

09:00 AM PST

Learn the winning strategy for a high GRE score — what do people who reach a high score do differently? We're going to share insights, tips and strategies from data we've collected from over 50,000 students who used examPAL.
• ### Free GMAT Strategy Webinar

January 19, 2019

January 19, 2019

07:00 AM PST

09:00 AM PST

Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

# A certain galaxy is known to comprise approximately 4 x 10^11 stars. O

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52161
A certain galaxy is known to comprise approximately 4 x 10^11 stars. O  [#permalink]

### Show Tags

06 Oct 2014, 13:45
00:00

Difficulty:

5% (low)

Question Stats:

84% (01:28) correct 16% (02:06) wrong based on 82 sessions

### HideShow timer Statistics

Tough and Tricky questions: Ratios

A certain galaxy is known to comprise approximately 4 x 10^11 stars. Of every 50 million of these stars, one is larger in mass than our sun. Approximately how many stars in this galaxy are larger than the sun?

A. 800
B. 1,250
C. 8,000
D. 12,000
E. 80,000

_________________
Board of Directors
Joined: 17 Jul 2014
Posts: 2600
Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
A certain galaxy is known to comprise approximately 4 x 10^11 stars. O  [#permalink]

### Show Tags

06 Oct 2014, 13:58
1
4*10^11
50 mln = 5*10^7

we divide 10^11 by 10^7 and we get (10^4)*4 = 40,000 and divide by 5. the result is 8,000 (c)
SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1823
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
A certain galaxy is known to comprise approximately 4 x 10^11 stars. O  [#permalink]

### Show Tags

Updated on: 07 Oct 2014, 00:18

$$\frac{4 * 10^{11}}{50 * 10^6} = 8 * 10^3 = 8000$$
_________________

Kindly press "+1 Kudos" to appreciate

Originally posted by PareshGmat on 06 Oct 2014, 18:02.
Last edited by PareshGmat on 07 Oct 2014, 00:18, edited 1 time in total.
Manager
Joined: 20 Dec 2013
Posts: 231
Location: India
Re: A certain galaxy is known to comprise approximately 4 x 10^11 stars. O  [#permalink]

### Show Tags

06 Oct 2014, 22:10
PareshGmat wrote:

$$\frac{4 * 10^{11}}{50 * 10^5} = 8 * 10^3 = 8000$$
.

A million has 6 zeros. I guess there is a typo!
Manager
Joined: 10 Sep 2014
Posts: 97
Re: A certain galaxy is known to comprise approximately 4 x 10^11 stars. O  [#permalink]

### Show Tags

12 Nov 2014, 10:46
I have a different approach to these problems. I wrote out 4x10^11 and 50 million right under it so that I could quickly divide.

400,000,000,000
50,000,000

4x10^11 is 400 billion. 400 billion is 400,000 millions. 400,000/50 = 8,000

Senior Manager
Status: Math is psycho-logical
Joined: 07 Apr 2014
Posts: 416
Location: Netherlands
GMAT Date: 02-11-2015
WE: Psychology and Counseling (Other)
Re: A certain galaxy is known to comprise approximately 4 x 10^11 stars. O  [#permalink]

### Show Tags

15 Feb 2015, 14:06
A similar solution:

$$4*10^4 = 5*10^7x$$ (x because we are told "of every 50 mil of these stars). So,

$$x =$$ $$\frac{4*10^4}{5*10^7}$$

$$x =$$ $$\frac{4}{5}$$ * $$10^4$$

$$x =$$ $$\frac{40000}{5}$$

$$x = 8000$$
EMPOWERgmat Instructor
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 13330
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Re: A certain galaxy is known to comprise approximately 4 x 10^11 stars. O  [#permalink]

### Show Tags

07 Feb 2018, 11:20
Hi All,

This question is really just about simplifying a fraction. You can either write the given numbers in Scientific Notation OR you can write out all of the zeroes and cancel them out.

Based on the information in the prompt, we're asked to simplify the following fraction:

(4 x 10^11)/(50,000,000)

We can rewrite the denominator as: (5 x 10^7)...

(4 x 10^11)/(5 x 10^7)

Now we can simplify the Scientific Notation....

(4 x 10^4) /(5) =

40,000/5 = 8,000

GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

# Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save \$75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****

Re: A certain galaxy is known to comprise approximately 4 x 10^11 stars. O &nbs [#permalink] 07 Feb 2018, 11:20
Display posts from previous: Sort by