It is currently 12 Dec 2017, 14:04

Close

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
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.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

(0.0036)(2.8) / (0.04)(0.1)(0.003) =

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

2 KUDOS received
Manager
Manager
avatar
Joined: 02 Dec 2012
Posts: 178

Kudos [?]: 3647 [2], given: 0

(0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 07 Dec 2012, 02:52
2
This post received
KUDOS
19
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

70% (01:16) correct 30% (01:21) wrong based on 1745 sessions

HideShow timer Statistics

\(\frac{(0.0036)(2.8)}{(0.04)(0.1)(0.003)}=\)

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084
[Reveal] Spoiler: OA

Kudos [?]: 3647 [2], given: 0

Expert Post
6 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 42571

Kudos [?]: 135384 [6], given: 12691

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 07 Dec 2012, 02:58
6
This post received
KUDOS
Expert's post
12
This post was
BOOKMARKED
Walkabout wrote:
(0.0036)(2.8) / (0.04)(0.1)(0.003) =

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084


\(\frac{0.0036*2.8}{0.04*0.1*0.003}=\frac{(36*10^{-4})*(28*10^{-1})}{(4*10^{-2})(1*10^{-1})*(3*10^{-3})}=\frac{36*28*10^{(-4-1)}}{4*3*10^{(-2-1-3)}}=84*10=840\).

Answer: A.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 135384 [6], given: 12691

5 KUDOS received
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1849

Kudos [?]: 2785 [5], given: 193

Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 13 Jun 2013, 01:40
5
This post received
KUDOS
While reading the problem, I re-wrote in the following way:
36/10000 * 28/10 * 100 / 4 * 10/1 * 1000/3
Simplifying further, Answer = A = 840
_________________

Kindly press "+1 Kudos" to appreciate :)

Kudos [?]: 2785 [5], given: 193

2 KUDOS received
Intern
Intern
avatar
Joined: 29 Mar 2014
Posts: 14

Kudos [?]: 9 [2], given: 23

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 24 Feb 2015, 11:26
2
This post received
KUDOS
1
This post was
BOOKMARKED
Walkabout wrote:
(0.0036)(2.8) / (0.04)(0.1)(0.003) =

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084


With these kinds of equations the best thing to do is move the decimal places to the right, remember, what you move in the numerator has to occur in the denominator.

1) ORIGINAL EQUATION: (0.0036)(2.8) / (0.04)(0.1)(0.003)

2) MOVE 2.8 TWO PLACES TO THE RIGHT AND MOVE 0.04 TWO PLACES TO THE RIGHT, EQUATION THEN BECOMES: (0.0036)(280) / (4)(0.1)(0.003)
YOU CAN NOW DIVIDE 280 BY 4 - CANCEL OUT THE FOUR AND THE 280 BECOMES 70

3) MOVE 0.0036 ONE PLACE TO THE RIGHT AND MOVE 0.1 IN THE DENOMINATOR ONE PLACE TO THE RIGHT, EQUATION THEN BECOMES: (0.036) (70) / (1) (0.003)

4) AGAIN MOVE 0.036 TWO PLACES TO THE RIGHT AND MOVE 0.003 TWO PLACES TO THE RIGHT, EQUATION THEN BECOMES: (36)(70) / (1)(3)

5) CANCEL OUT THE THREE AND THE 36 TO FURTHER SIMPLIFY, YOUR EQUATION THEN BECOMES 12*70 = 840 WHICH IS ANSWET CHOICE A

Kudos [?]: 9 [2], given: 23

1 KUDOS received
Manager
Manager
avatar
B
Joined: 23 May 2013
Posts: 189

Kudos [?]: 120 [1], given: 42

Location: United States
Concentration: Technology, Healthcare
Schools: Stanford '19 (M)
GMAT 1: 760 Q49 V45
GPA: 3.5
GMAT ToolKit User
Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 25 Aug 2014, 06:25
1
This post received
KUDOS
With questions like this, take a look at the answers first. Notice the only distinction between the answers is the factor of ten; thus, an exact calculation is not necessary to solve the problem, just a quick approximation.

.0036*2.8 is ~.0036*3, which can be approximated to .01.

.04*.1 = .004

Thus we have (.01)/(.004*.003). We can cancel out the powers of ten to give us 1/(.4*.003), which is 1/(.0012).

.0012 in fraction form is 12/10,000. Thus, our answer is can be given as 10,000/12.

840 is the only answer that comes close. Answer:A

Using the approximation method you can easily solve this question in 1:30 - 2:00.

Kudos [?]: 120 [1], given: 42

1 KUDOS received
Intern
Intern
avatar
Joined: 26 Sep 2011
Posts: 1

Kudos [?]: 2 [1], given: 0

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 08 Oct 2015, 07:44
1
This post received
KUDOS
1
This post was
BOOKMARKED
I found my approach to be the quickest available and I'd like to share it with you guys:

(0.0036 x 2.8)/(0.04x0.1x0.003)
-> expand numerator and denominator by 10^6 (since there are 5 decimal places in the numerator and 6 decimal places in the denominator)
this yields:
(360x28)/(4x1x3)
-> cancel
(120x7)/(1x1x1)= 120x7 = 840 -> A

Kudos [?]: 2 [1], given: 0

1 KUDOS received
Intern
Intern
User avatar
B
Joined: 09 Mar 2016
Posts: 49

Kudos [?]: 5 [1], given: 50

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 25 Nov 2017, 03:35
1
This post received
KUDOS
Walkabout wrote:
\(\frac{(0.0036)(2.8)}{(0.04)(0.1)(0.003)}=\)

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084



I multiplied all numbers by 10,000 to get integers hence

36 * 28000 / 400 * 1000* 30 = 210/ 2500 which is 0.084. Then answer is multiplied by 10,000.

0.084 *10,000 = 840

Answer A

Do you guys think it is a the fastest and the most accurate way ? :)

Kudos [?]: 5 [1], given: 50

Intern
Intern
avatar
Joined: 04 Aug 2013
Posts: 6

Kudos [?]: 7 [0], given: 8

Concentration: Sustainability, Entrepreneurship
WE: Architecture (Energy and Utilities)
GMAT ToolKit User
Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 29 Oct 2013, 15:13
I calculated the power of 10.
It was 10^5 / 10^-6.
Hence the ans. will end with 10^1. Its only A.

Kudos [?]: 7 [0], given: 8

Manager
Manager
avatar
Joined: 07 Apr 2014
Posts: 136

Kudos [?]: 33 [0], given: 81

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 11 Sep 2014, 05:31
Walkabout wrote:
(0.0036)(2.8) / (0.04)(0.1)(0.003) =

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084




36(28)*10^-5 / 12 * 10^-6


84 /10^-1 = 840

Kudos [?]: 33 [0], given: 81

Intern
Intern
avatar
Joined: 15 Sep 2014
Posts: 2

Kudos [?]: [0], given: 5

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 23 Sep 2014, 10:09
I think there is mistake in the last part of the solution.
84 /10^-1 = 840 . This should be 8.4 not 840.
84/10^1 = 840.

Let me know if my understanding is correct.

Kudos [?]: [0], given: 5

Manager
Manager
avatar
Joined: 07 Apr 2014
Posts: 136

Kudos [?]: 33 [0], given: 81

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 23 Sep 2014, 23:49
preetnyc wrote:
I think there is mistake in the last part of the solution.
84 /10^-1 = 840 . This should be 8.4 not 840.
84/10^1 = 840.

Let me know if my understanding is correct.



1/10^-1 = 10.. (the way i used power without symbol might create problem)

check below url..

Reciprocal in http://gmatclub.com/forum/math-number-theory-88376.html

Kudos [?]: 33 [0], given: 81

SVP
SVP
User avatar
B
Joined: 06 Nov 2014
Posts: 1904

Kudos [?]: 549 [0], given: 23

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 28 Feb 2015, 07:26
Walkabout wrote:
(0.0036)(2.8) / (0.04)(0.1)(0.003) =

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084


Given that (0.0036)(2.8) / (0.04)(0.1)(0.003)
= [(36/1000)(28/10)] / [(4/100)(1/10)(3/100)]
= [(36*28)/(10000)] / [(4*1*3)/(100*10*100)]
= [(36*28)/(4*1*3)] * [(100*10*100) / 10000]
= (3*28) * 10
= 840
Hence option A

--
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

Kudos [?]: 549 [0], given: 23

Manager
Manager
User avatar
Joined: 18 Aug 2014
Posts: 129

Kudos [?]: 79 [0], given: 36

Location: Hong Kong
Schools: Mannheim
Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 10 Oct 2015, 02:36
OptimusPrepJanielle wrote:
Walkabout wrote:
(0.0036)(2.8) / (0.04)(0.1)(0.003) =

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084


Given that (0.0036)(2.8) / (0.04)(0.1)(0.003)
= [(36/1000)(28/10)] / [(4/100)(1/10)(3/100)]
= [(36*28)/(10000)] / [(4*1*3)/(100*10*100)]
= [(36*28)/(4*1*3)] * [(100*10*100) / 10000]
= (3*28) * 10
= 840
Hence option A

--
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


0.0036 = 36/10,000

Kudos [?]: 79 [0], given: 36

Manager
Manager
User avatar
B
Joined: 30 Dec 2015
Posts: 90

Kudos [?]: 23 [0], given: 153

GPA: 3.92
WE: Engineering (Aerospace and Defense)
Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 16 Jan 2016, 17:01
Not sure if this is the right way to approach the answer, since the answer choices have big separation, I decided to approximate.
(0.0036)(2.8) / (0.04)(0.1)(0.003) = (4∗10^−3)∗(3)/[(4∗10^−2)(1∗10^−1)∗(3∗10^−3)] = 1*10^3 = ~1000
Closest Ans to 1000 is C: 840
_________________

If you analyze enough data, you can predict the future.....its calculating probability, nothing more!

Kudos [?]: 23 [0], given: 153

Board of Directors
User avatar
P
Joined: 17 Jul 2014
Posts: 2697

Kudos [?]: 447 [0], given: 207

Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
GMAT ToolKit User Premium Member Reviews Badge
Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 07 Sep 2016, 07:17
i put everything in fractions, and it helped much.
[(36*28)/10,000 * 10] * (100*10*1000)/(4*1*3)

now, simplify and get 7*12*10 = 840
A

Kudos [?]: 447 [0], given: 207

Expert Post
Math Expert
User avatar
D
Joined: 02 Aug 2009
Posts: 5341

Kudos [?]: 6107 [0], given: 121

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) = [#permalink]

Show Tags

New post 25 Nov 2017, 04:05
Walkabout wrote:
\(\frac{(0.0036)(2.8)}{(0.04)(0.1)(0.003)}=\)

(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084



No need to calculate for non-zero terms as it has to be 84..
check the decimal points..
Numerator has 5 and denominator has 6, so answer should be 6-5 =1 digit before decimal point
or 8.4
_________________

Absolute modulus :http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

Kudos [?]: 6107 [0], given: 121

Re: (0.0036)(2.8) / (0.04)(0.1)(0.003) =   [#permalink] 25 Nov 2017, 04:05
Display posts from previous: Sort by

(0.0036)(2.8) / (0.04)(0.1)(0.003) =

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.