BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

standard deviation: normal distribution

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Master | Next Rank: 500 Posts
Posts: 181
Joined: Fri Feb 17, 2012 9:36 amFollowed by: 1 member
Thanked: 1 times
GMAT Score:620
by heymayank08 » Sun Mar 18, 2012 1:14 am
pls help how to tackle the normal distribution questions in standard deviation.

rough eg: mean is 4 and SD is 2 then calculate value after 2 standard deviations the mean.(the data is symmetric about the mean).
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Legendary Member
Posts: 1084
Joined: Fri Apr 15, 2011 2:33 pmFollowed by: 21 members
Thanked: 158 times

by pemdas » Sun Mar 18, 2012 2:09 am
plz follow explanations for realistic example:
akhilsuhag wrote:The average (arithmetic mean) of a normal distribution of a school's test scores is 65, and standard deviation of the distribution is 6.5. A student scoring a 78 on the exam is in what percentile of the school?

[spoiler]OA: 98[/spoiler]
pemdas wrote:The percentages are valid for any question involving a normal distribution, and one should memorize them as 34: 14 : 2. The percentages correspond to the 1st, 2nd, and 3rd standard deviations on each side of the mean. A student scoring 78 on the exam is placed two standard deviations on the right side of the mean, that is 50% (mean) + 34% + 14% = 98%
you can find details at this link https://www.beatthegmat.com/mean-and-sta ... tml#402966
Success doesn't come overnight!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 181
Joined: Fri Feb 17, 2012 9:36 amFollowed by: 1 member
Thanked: 1 times
GMAT Score:620

by heymayank08 » Sun Mar 18, 2012 5:21 am
thanx..i was looking for the %age distribution that u jst gave.
i think it solves my problem :)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1