Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
23 Aug 2017, 01:24
Kudos
Bookmarks
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
45%
(medium)
Question Stats:
62% (01:24) correct
38%
(01:33)
wrong
based on 427
sessions
History
Date
Time
Result
Not Attempted Yet
Which of the following is the closest to \(11*10^{20}–9*10^{10}\)?
A. \(10^2\)
B. \(10^7\)
C. \(10^{10}\)
D. \(10^{20}\)
E. \(10^{21}\)
A. \(10^2\)
B. \(10^7\)
C. \(10^{10}\)
D. \(10^{20}\)
E. \(10^{21}\)
sashiim20
Joined: 04 Dec 2015
Last visit: 05 Jun 2024
Posts: 608
Given Kudos: 276
Location: India
Concentration: Technology, Strategy
Schools: ISB '19 IIMB IIMA XLRI HEC Sept19 intake Rotman '21 NUS '21 NTU '20 Trinity MBA '20 Bocconi '21 Smurfit "21
WE:Information Technology (Consulting)
Schools: ISB '19 IIMB IIMA XLRI HEC Sept19 intake Rotman '21 NUS '21 NTU '20 Trinity MBA '20 Bocconi '21 Smurfit "21
Posts: 608
23 Aug 2017, 02:34
Kudos
Bookmarks
MathRevolution
\(11*10^{20}–9*10^{10}\)
We can use approximate value. Hence we can use \(10\) in place of \(11\) and \(10\) in place of \(9\).
\((10*10^{20}) – (10*10^{10})\)
\(10^{(20+1)}–10^{(10+1)}\)
\(10^{21}–10^{11}\)
\(10^{11}(10^{10}–1)\)
\(1\) is very small value compared to \(10^{10}\). Hence \(1\) can be ignored. Therefore \((10^{10}–1) =\) approximately \(= 10^{10}\)
\((10^{11})(10^{10})\)
\(10^{(11+10)}\) \(= 10^{21}\)
Answer (E)...
_________________
Please Press "+1 Kudos" to appreciate.
General Discussion
23 Aug 2017, 05:39
Kudos
Bookmarks
We have been asked to find the value of the expression \(11*10^{20}–9*10^{10}\)
\(11*10^{20}–9*10^{10}\)
= \(11*10^{10}*10^{10} – 9*10^{10}\)
= \(10^{10}(11*10^{10} – 9)\)
Since we need an approximate value and the overall expression has extremely large numbers,
we can assume both 11 and 9 to be equal to 10
The expression now becomes \(10^{10}(10*10^{10} – 10) = 10^{10}*10^1(10^{10} – 1) = 10^{10+1}(10^{10} – 1)\) = \(10^{11}(10^{10})\)
Since a difference of 1 does not influence the value of the expression to that extent, the value must be \(10^{21}\) approximately (Option E)
\(11*10^{20}–9*10^{10}\)
= \(11*10^{10}*10^{10} – 9*10^{10}\)
= \(10^{10}(11*10^{10} – 9)\)
Since we need an approximate value and the overall expression has extremely large numbers,
we can assume both 11 and 9 to be equal to 10
The expression now becomes \(10^{10}(10*10^{10} – 10) = 10^{10}*10^1(10^{10} – 1) = 10^{10+1}(10^{10} – 1)\) = \(10^{11}(10^{10})\)
Since a difference of 1 does not influence the value of the expression to that extent, the value must be \(10^{21}\) approximately (Option E)
