Last visit was: 19 Nov 2025, 08:45 It is currently 19 Nov 2025, 08:45
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
Sub 505 Level|   Arithmetic|   Roots|            
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 19 Nov 2025
Posts: 105,389
Own Kudos:
778,277
 [4]
Given Kudos: 99,977
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 105,389
Kudos: 778,277
 [4]
1
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
avatar
linhmba
Joined: 17 Apr 2019
Last visit: 16 Jun 2020
Posts: 6
Own Kudos:
52
 [1]
Given Kudos: 29
Posts: 6
Kudos: 52
 [1]
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
User avatar
Abhishek009
User avatar
Board of Directors
Joined: 11 Jun 2011
Last visit: 18 Jul 2025
Posts: 5,934
Own Kudos:
5,327
 [1]
Given Kudos: 463
Status:QA & VA Forum Moderator
Location: India
GPA: 3.5
WE:Business Development (Commercial Banking)
Posts: 5,934
Kudos: 5,327
 [1]
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
User avatar
BrentGMATPrepNow
User avatar
Major Poster
Joined: 12 Sep 2015
Last visit: 31 Oct 2025
Posts: 6,739
Own Kudos:
Given Kudos: 799
Location: Canada
Expert
Expert reply
Posts: 6,739
Kudos: 35,344
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
What is the value of \(\sqrt{17} + \sqrt{47}\), to the nearest whole number?

A. 8
B. 11
C. 12
D. 15
E. 32

\(\sqrt{16} = 4\)
\(\sqrt{25} = 5\)
So, \(\sqrt{17} ≈ 4.1\)

\(\sqrt{36} = 6\)
\(\sqrt{49} = 7\)
So, \(\sqrt{47} ≈ 6.8\)

So, \(\sqrt{17} + \sqrt{47}≈4.1 + 6.8≈10.9\)

Answer: B
User avatar
CrackverbalGMAT
User avatar
Major Poster
Joined: 03 Oct 2013
Last visit: 19 Nov 2025
Posts: 4,844
Own Kudos:
Given Kudos: 225
Affiliations: CrackVerbal
Location: India
Expert
Expert reply
Posts: 4,844
Kudos: 8,945
Kudos
Add Kudos
Bookmarks
Bookmark this Post
A technique that I adopt when I have to deal with non-perfect square is to think of bigger perfect squares and then introduce decimals.

Now, instead of 17, let’s think of 1700. We know \(40^2\) = 1600 and \(41^2\) = 1681. Therefore, √1700 is just a shade above 41.
It is now easy for you to see that √17 will be a shade above 4.1

Similarly, \(70^2\) = 4900, so √4700 will be very close to 69 (less than 69).
So, √47 will be a shade below 6.9.

Therefore, √17 + √47 ≈ 4.1 + 6.9 = 11.

The correct answer option is B.

Hope that helps!
Aravind B T
User avatar
bot00078
Joined: 08 Mar 2025
Last visit: 07 Nov 2025
Posts: 36
Own Kudos:
Given Kudos: 14
GMAT Focus 1: 345 Q70 V66 DI62
GMAT Focus 1: 345 Q70 V66 DI62
Posts: 36
Kudos: 4
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
What is the value of \(\sqrt{17} + \sqrt{47}\), to the nearest whole number?

A. 8
B. 11
C. 12
D. 15
E. 32
YO,
So Here Just Check the nearest Roots
\sqrt{16} which is 4 so there is \sqrt{17 } is a bit more than 4 i apporx it as 4.25
\sqrt{49} Which is 7 so here also \sqrt{47} which is <7 may be 6.50 or somthing, where the options are easy so the nearest Number is 11
Moderators:
Math Expert
105389 posts
Tuck School Moderator
805 posts