Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 563 reviewsTarget Test Prep

MGMAT Found of Math Fractions | Simplify: (√3/2)-(√3/8)

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Wed Oct 26, 2016 8:44 am
by mkofron » Sat Nov 05, 2016 4:42 pm
Simplify: (√3/2)−(√3/8)

Why does the answer explanation not use √8 as the common denominator? Is this illegal?


"Treat this as a standard fraction subtraction problem: find common denominators so that you can subtract. Begin by splitting the square root symbols across the numerator and denominator."
You do not have the required permissions to view the files attached to this post.
Top
Join the discussion
Source: — Problem Solving |
User avatar
Master | Next Rank: 500 Posts
Posts: 335
Joined: Mon Mar 21, 2011 11:31 pmFollowed by: 2 members
Location: Australia / India
Thanked: 37 times

by melguy » Sat Nov 05, 2016 6:14 pm
In this problem you have to find the LCM like any other fraction problem.

You would make your life difficult if you take the numerical approach. Considering we have to solve the problem in under two minutes we are supposed to find the easiest approach which would be to simply use √8 x √2 giving us √16 (i.e. 4).
Top
Join the discussion

GMAT/MBA Expert

User avatar
Elite Legendary Member
Posts: 10391
Joined: Sun Jun 23, 2013 6:38 pmFollowed by: 511 members
Location: Palo Alto, CA
Thanked: 2867 times
GMAT Score:800

by [email protected] » Sat Nov 05, 2016 8:46 pm
Hi mkofron,

YES - you could use root8 as the common denominator. Did you try to do so? How many math 'steps' did it take you to get to the correct answer (and when you compare that work to the work shown in this explanation, which option looked easier?)?

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Top
Join the discussion
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Wed Oct 26, 2016 8:44 am

by mkofron » Sat Nov 05, 2016 9:12 pm
I did try the root8 method but I could not manipulate the expressions to get to any of the answer choices. :| Which tells me I have a deficiency somewhere....I get the that root16 is quicker but I am also trying to figure out why I can't make the the root8 method work.

Thanks,
Matt
Top
Join the discussion

GMAT/MBA Expert

User avatar
Elite Legendary Member
Posts: 10391
Joined: Sun Jun 23, 2013 6:38 pmFollowed by: 511 members
Location: Palo Alto, CA
Thanked: 2867 times
GMAT Score:800

by [email protected] » Sun Nov 06, 2016 12:19 pm
Hi Matt,

Could you post a pic/screen capture of your work so that I can see where you got 'stuck?'

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Top
Join the discussion
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Wed Oct 26, 2016 8:44 am

by mkofron » Sun Nov 06, 2016 2:01 pm
Hey Rich,

Thanks for getting back. Here is how I tried to do it.
Image

You can see I made a silly mistake in the denominator (sqrt 18 instead of sqrt 8) and corrected it before I took this photo. I appreciate the help.

Regards,
Matt
Top
Join the discussion
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Wed Oct 26, 2016 8:44 am

by mkofron » Sun Nov 06, 2016 3:18 pm
OK, I see what I neglected to do. I just needed to get the square root out of the denominator in my step #6. My original answer choice is equivalent to the correct answer just not as simplified.
Top
Join the discussion