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 →

please help me out

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 82
Joined: Sat Mar 26, 2011 4:59 am
Thanked: 4 times
by B166418 » Wed Jun 29, 2011 10:54 am
For a certain examination,a score of 58 was 2 standard deviations below the mean,and a score of 98 was 3 standard deviations above the mean .What was the mean score for the examination ?

A 74
B 76
C 78
D 80
E 82
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Legendary Member
Posts: 1448
Joined: Tue May 17, 2011 9:55 amFollowed by: 53 members
Location: India
Thanked: 375 times

by Frankenstein » Wed Jun 29, 2011 11:05 am
Hi,
If 'm' is the mean and 'd' is the standard deviation, from the given data
m - 2d = 58
m + 3d = 98
Solving, we get d= 8 and m = 74

Hence, A
Cheers!

Things are not what they appear to be... nor are they otherwise
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Senior | Next Rank: 100 Posts
Posts: 82
Joined: Sat Mar 26, 2011 4:59 am
Thanked: 4 times

by B166418 » Wed Jun 29, 2011 11:31 am
Wow!!! and I was applying standard deviation and mean formulas in this problem
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 401
Joined: Tue May 24, 2011 1:14 amFollowed by: 5 members
Thanked: 37 times

by MBA.Aspirant » Wed Jun 29, 2011 1:43 pm
B166418 wrote:For a certain examination,a score of 58 was 2 standard deviations below the mean,and a score of 98 was 3 standard deviations above the mean .What was the mean score for the examination ?

A 74
B 76
C 78
D 80
E 82
m - 2d= 58

m + 3d = 98

5d = 40

d = 8

m = 98 - 3 (8) = 74
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1