Last visit was: 15 Nov 2024, 10:23 It is currently 15 Nov 2024, 10:23

Close

GRE Prep 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 GRE 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
Verbal Expert
Joined: 18 Apr 2015
Posts: 29961
Own Kudos [?]: 36231 [2]
Given Kudos: 25905
Send PM
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Own Kudos [?]: 12189 [3]
Given Kudos: 136
Send PM
Intern
Intern
Joined: 08 Apr 2021
Posts: 12
Own Kudos [?]: 1 [0]
Given Kudos: 29
Send PM
Verbal Expert
Joined: 18 Apr 2015
Posts: 29961
Own Kudos [?]: 36231 [0]
Given Kudos: 25905
Send PM
Re: rs = \sqrt 3 [#permalink]
Expert Reply
I am not quite sure where is the division indicated by you Sir

Could you point out ??
GRE Instructor
Joined: 24 Dec 2018
Posts: 1065
Own Kudos [?]: 1424 [1]
Given Kudos: 24
Send PM
rs = \sqrt 3 [#permalink]
1
condition: \(rs=\sqrt{3}\)

Quantity A:\(\frac{2r \sqrt{12}}{r^2s \sqrt{72}}\) = \(\frac{2r \sqrt{12}}{rrs \sqrt{72}}\) = \(\frac{2r \sqrt{4 \times 3}}{r \sqrt{3} \sqrt{9 \times 8}}\) = \(\frac{2.2 \sqrt{3}}{\sqrt{3}.3.2\sqrt{2}}\) = \(\frac{2}{3\sqrt{2}}\) = \(\frac{\sqrt{2}}{3}\)


Quantity B: \(\frac{14rs^2}{42s}\) = \(\frac{14rss}{42s}\) = \(\frac{14rs}{42}\) = \(\frac{14rs}{7 \times 6}\) = \(\frac{2rs}{6}\) = \(\frac{2\sqrt{3}}{2 \times 3}\) = \(\frac{\sqrt{3}}{3}\)


Clearly Quantity B is greater.
GRE Instructor
Joined: 24 Dec 2018
Posts: 1065
Own Kudos [?]: 1424 [1]
Given Kudos: 24
Send PM
rs = \sqrt 3 [#permalink]
1
Aprazors wrote:
GreenlightTestPrep wrote:
Carcass wrote:
\(rs = \sqrt{3}\)

Quantity A
Quantity B
\(\frac{2r \sqrt{12}}{r^2s \sqrt{72}}\)
\(\frac{14rs^2}{42s}\)


A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.


\(\sqrt{12}=(\sqrt{4})(\sqrt{3})=2\sqrt{3}\)
\(\sqrt{72}=(\sqrt{36})(\sqrt{2})=6\sqrt{2}\)

We get:
QUANTITY A: \(\frac{2r \sqrt{12}}{r^2s \sqrt{72}}=\frac{(2r)(2 \sqrt{3})}{(r)(rs)(6\sqrt{2})}=\frac{(4r)(\sqrt{3})}{(r)(\sqrt{3})(6\sqrt{2})}=\frac{4}{6\sqrt{2}}=\frac{2}{3\sqrt{2}}\)

QUANTITY B: \(\frac{14rs^2}{42s}=\frac{14(rs)(s)}{42s}=\frac{rs}{3}=\frac{\sqrt{3}}{3}\)

At this point, we can use matching operations

Multiply both quantities by 3 to get:
QUANTITY A: \(\frac{2}{\sqrt{2}}\)

QUANTITY B: \(\sqrt{3}\)



Multiply both quantities by \(\sqrt{2}\) to get:
QUANTITY A: \(2\)

QUANTITY B: \(\sqrt{6}\)

Since \(\sqrt{6}>2\), the correct answer is B


RELATED VIDEO FROM MY COURSE




for quantity A why not just divide by 12 to 72 so it will become root(1/6)



Yes. You can follow that route too. Then the fraction becomes \(\frac{2r\sqrt{1}}{r^2s.\sqrt{6}} = \frac{2}{rs.\sqrt{6}} = \frac{2}{\sqrt{3}.\sqrt{6}} = \frac{2}{\sqrt{18}} = \frac{2}{\sqrt{9 \times 2}} = \frac{2}{3.\sqrt{2}} = \frac{\sqrt{2}}{3}\)

You will get the same answer.
Prep Club for GRE Bot
rs = \sqrt 3 [#permalink]
Moderators:
GRE Instructor
78 posts
GRE Forum Moderator
37 posts
Moderator
1111 posts
GRE Instructor
234 posts

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