Author 
Message 
TAGS:

Hide Tags

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 5062
GPA: 3.82

√{(4.8)(10^9)} is closest to which of the following? A. 7,000 [#permalink]
Show Tags
24 Mar 2016, 17:01
1
This post received KUDOS
Expert's post
1
This post was BOOKMARKED
Question Stats:
67% (00:44) correct 33% (00:56) wrong based on 314 sessions
HideShow timer Statistics
√{(4.8)(10^9)} is closest to which of the following? A. 7,000 B. 70,000 C. 14,000 D. 22,000 E. 220,000 * A solution will be posted in two days.
Official Answer and Stats are available only to registered users. Register/ Login.
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The oneandonly World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only $79 for 3 month Online Course" "Free Resources30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons  try it yourself"



Math Expert
Joined: 02 Aug 2009
Posts: 5724

Re: √{(4.8)(10^9)} is closest to which of the following? A. 7,000 [#permalink]
Show Tags
24 Mar 2016, 20:38
MathRevolution wrote: √{(4.8)(10^9)} is closest to which of the following?
A. 7,000 B. 70,000 C. 14,000 D. 22,000 E. 220,000
* A solution will be posted in two days. first lets get the number to slighly more friendly expression\(\sqrt{(4.8)*10^9}\) = \(\sqrt{48*10^8}\) 48 is nearly equal to 49 which is \(7^2\).. so ans = \(7*10^4\) B
_________________
Absolute modulus :http://gmatclub.com/forum/absolutemodulusabetterunderstanding210849.html#p1622372 Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
GMAT online Tutor



SVP
Joined: 12 Sep 2015
Posts: 2154
Location: Canada

Re: √{(4.8)(10^9)} is closest to which of the following? A. 7,000 [#permalink]
Show Tags
25 Mar 2016, 12:16
MathRevolution wrote: √{(4.8)(10^9)} is closest to which of the following?
A. 7,000 B. 70,000 C. 14,000 D. 22,000 E. 220,000
We can apply the rule that says: √xy = (√x)(√y) √{(4.8)(10^9)} = √{(4.8)(10^1)(10^8)} = √{(48)(10^8)} = (√48)(√10^8) [applied rule from above]= (7)(10^4) = (7)(10,000) = 70,000 Answer: B For more on the rule √xy = (√x)(√y), see this free video: https://www.gmatprepnow.com/module/gmat ... video/1037
_________________
Brent Hanneson – Founder of gmatprepnow.com



Intern
Joined: 18 Jul 2015
Posts: 17
WE: Analyst (Consumer Products)

√{(4.8)(10^9)} is closest to which of the following? A. 7,000 [#permalink]
Show Tags
25 Mar 2016, 23:19
\(\sqrt{{(4.8)(10^9)}}\)
\(\sqrt{{(48/10)(10^9)}}\)
\(\sqrt{{(48)(10^8)}}\)
\(\sqrt{{(4 * 12)(10^8)}}\)
Apply the square root:
\((2 * 2\sqrt{3})(10^4)\)
Now, \(\sqrt{3}\) = 1.73
Therefore, \(2 * 2 * 1.73 * 10^4\) = 69200 ~ 70,000
Answer: B



Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 5062
GPA: 3.82

Re: √{(4.8)(10^9)} is closest to which of the following? A. 7,000 [#permalink]
Show Tags
27 Mar 2016, 01:39
√{(4.8)(10^9)} is closest to which of the following? A. 7,000 B. 70,000 C. 14,000 D. 22,000 E. 220,000 > √{(4.8)(10^9)}=√{(48)(10^8)}=√{(49)(10^8)}=√{(7^2)(10^4)}^2 =(7)(10^4)=70,000. Therefore, the answer is B.
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The oneandonly World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only $79 for 3 month Online Course" "Free Resources30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons  try it yourself"



Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 5062
GPA: 3.82

Re: √{(4.8)(10^9)} is closest to which of the following? A. 7,000 [#permalink]
Show Tags
28 Mar 2016, 04:53
√{(4.8)(10^9)} is closest to which of the following? A. 7,000 B. 70,000 C. 14,000 D. 22,000 E. 220,000 > √{(4.8)(10^9)}=√{(48)(10^8)}=√{(49)(10^8)}=√{(7^2)(10^4)^2}=(7)(10^4)=70,000 Thus, the answer is B.
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The oneandonly World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only $79 for 3 month Online Course" "Free Resources30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons  try it yourself"



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 2319
Location: United States (CA)

Re: √{(4.8)(10^9)} is closest to which of the following? A. 7,000 [#permalink]
Show Tags
24 Oct 2017, 06:08
MathRevolution wrote: √{(4.8)(10^9)} is closest to which of the following?
A. 7,000 B. 70,000 C. 14,000 D. 22,000 E. 220,000 First, notice that in order to easily take the square root, we want to reexpress 4.8 x 10^9 as 48 x 10^8. Now we have: √{(4.8)(10^9)} = √{(48)(10^8)} = √48 x √10^8 ≈ √49 x √10^8 = 7 x 10^4 = 70,000 Answer: B
_________________
Scott WoodburyStewart
Founder and CEO
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions




Re: √{(4.8)(10^9)} is closest to which of the following? A. 7,000
[#permalink]
24 Oct 2017, 06:08






