GMAT Changed on April 16th - Read about the latest changes here

It is currently 24 Apr 2018, 16:05

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

(4.8*10^9)^1/2 is closest in value to

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

Hide Tags

6 KUDOS received
Intern
Intern
User avatar
B
Joined: 31 Aug 2014
Posts: 22
GMAT ToolKit User CAT Tests
(4.8*10^9)^1/2 is closest in value to [#permalink]

Show Tags

New post Updated on: 14 Sep 2015, 07:22
6
This post received
KUDOS
5
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

74% (00:39) correct 26% (00:47) wrong based on 224 sessions

HideShow timer Statistics

\(\sqrt{4.8*10^9}\) is closest in value to

(A) 2,200
(B) 70,000
(C) 220,000
(D) 7,000,000
(E) 22,000,000
[Reveal] Spoiler: OA

_________________

Please press+ 1kudos if you appreciate this post and for motivation !!


Originally posted by ske on 14 Sep 2015, 07:07.
Last edited by Bunuel on 14 Sep 2015, 07:22, edited 1 time in total.
Renamed the topic and edited the question.
5 KUDOS received
Manager
Manager
avatar
Joined: 10 Aug 2015
Posts: 103
GMAT ToolKit User
Re: (4.8*10^9)^1/2 is closest in value to [#permalink]

Show Tags

New post 14 Sep 2015, 07:29
5
This post received
KUDOS
4
This post was
BOOKMARKED
ske wrote:
\(\sqrt{4.8*10^9}\) is closest in value to

(A) 2,200
(B) 70,000
(C) 220,000
(D) 7,000,000
(E) 22,000,000


Solution: \(\sqrt{4.8*10^9}\) = \(\sqrt{48*10^8}\) = \(\sqrt{49*10^8}\) = \(7*10^4\)

Option B
Intern
Intern
avatar
B
Joined: 04 Jun 2017
Posts: 8
Re: (4.8*10^9)^1/2 is closest in value to [#permalink]

Show Tags

New post 20 Sep 2017, 20:03
First method: Estimate

\(\sqrt{4.8 * 10^9}\) < \(\sqrt{10 * 10^9}\)
\(\sqrt{4.8 * 10^9}\) < 100,000

\(\sqrt{4.8 * 10^9}\) is definitely less than 100,000 but close to 100,000 => answer is B




Second method: Calculation

\(\sqrt{4.8 * 10^9}\) =
\(\sqrt{48 * 10^8}\) =

then take square roots of both parts:
\(\sqrt{48}\) * \(\sqrt{10^8}\) =
4\(\sqrt{3}\) * 10^4 =
4 * \(\sqrt{3}\) * 10,000 =
40,000 * 1.7 (I memorized that \(\sqrt{3}\) is approximately 1.7) =
~68,000 => answer is B
Expert Post
1 KUDOS received
Target Test Prep Representative
User avatar
G
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 2464
Location: United States (CA)
Re: (4.8*10^9)^1/2 is closest in value to [#permalink]

Show Tags

New post 20 Dec 2017, 08:44
1
This post received
KUDOS
Expert's post
ske wrote:
\(\sqrt{4.8*10^9}\) is closest in value to

(A) 2,200
(B) 70,000
(C) 220,000
(D) 7,000,000
(E) 22,000,000


√(4.8 x 10^9) is equivalent to √(48 x 10^8), which equals:

√48 x √10^8 = 4√3 x 10^4 = 4 x 1.7 x 10,000 = 68,000 or about 70,000.

Alternative solution:

√(4.8 x 10^9) is equivalent to √(48 x 10^8), which is about √(49 x 10^8). We choose the number 49 because 49 is a perfect square. Now let’s simplify √(49 x 10^8):

√49 x √10^8 = 7 x 10^4 = 70,000

Answer: B
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Senior Manager
Senior Manager
User avatar
G
Joined: 09 Mar 2016
Posts: 444
(4.8*10^9)^1/2 is closest in value to [#permalink]

Show Tags

New post 24 Feb 2018, 04:37
anudeep133 wrote:
ske wrote:
\(\sqrt{4.8*10^9}\) is closest in value to

(A) 2,200
(B) 70,000
(C) 220,000
(D) 7,000,000
(E) 22,000,000


Solution: \(\sqrt{4.8*10^9}\) = \(\sqrt{48*10^8}\) = \(\sqrt{49*10^8}\) = \(7*10^4\)

Option B



hello niks18 :) its weekend the weather is awesome, but still i need to ppractice a few quant questions :) can you please help :)

How mathematically do we call the process when from this \(\sqrt{4.8*10^9}\) we get this \(\sqrt{49*10^8}\) ? :? I mean exponent is changed and also 4.8 turned into 48

Another question I didnt understand the process of taking square root from this \(\sqrt{10^8}\) when we get this \(10^4\) what is the principle logic when exponent 8 is turned in 4 after taking square root

many thanks! :)
1 KUDOS received
PS Forum Moderator
avatar
D
Joined: 25 Feb 2013
Posts: 1059
Location: India
GPA: 3.82
GMAT ToolKit User Premium Member Reviews Badge CAT Tests
Re: (4.8*10^9)^1/2 is closest in value to [#permalink]

Show Tags

New post 24 Feb 2018, 05:04
1
This post received
KUDOS
1
This post was
BOOKMARKED
dave13 wrote:
anudeep133 wrote:
ske wrote:
\(\sqrt{4.8*10^9}\) is closest in value to

(A) 2,200
(B) 70,000
(C) 220,000
(D) 7,000,000
(E) 22,000,000


Solution: \(\sqrt{4.8*10^9}\) = \(\sqrt{48*10^8}\) = \(\sqrt{49*10^8}\) = \(7*10^4\)

Option B



hello niks18 :) its weekend the weather is awesome, but still i need to ppractice a few quant questions :) can you please help :)

How mathematically do we call the process when from this \(\sqrt{4.8*10^9}\) we get this \(\sqrt{49*10^8}\) ? :? I mean exponent is changed and also 4.8 turned into 48

Another question I didnt understand the process of taking square root from this \(\sqrt{10^8}\) when we get this \(10^4\) what is the principle logic when exponent 8 is turned in 4 after taking square root

many thanks! :)


Hi dave13

Query 1: \(4.8*10^9=4.8*10*10^8=48*10^8\)

Query 2: \(\sqrt{10^8}=\sqrt{(10^4)^2}=10^4\)

I will urge you to strengthen concepts of exponents before attempting these questions. Refer to GMAT Club free math book or any other good resource. This will help you gain more than simply understanding the solutions.
Re: (4.8*10^9)^1/2 is closest in value to   [#permalink] 24 Feb 2018, 05:04
Display posts from previous: Sort by

(4.8*10^9)^1/2 is closest in value to

  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®.