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 →

If two elements are dropped from set \(X =\{-10, -8, 0, 6, 7\},\) what will be the percentage change in its mean?

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 1622
Joined: Thu Mar 01, 2018 7:22 amFollowed by: 2 members
by Gmat_mission » Tue Nov 10, 2020 8:02 am

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty—

If two elements are dropped from set \(X =\{-10, -8, 0, 6, 7\},\) what will be the percentage change in its mean?

(1) The median of the set will remain the same.
(2) The range of the set will decrease by \(3.\)

Answer: B

Source: Manhattan GMAT
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Legendary Member
Posts: 2214
Joined: Fri Mar 02, 2018 2:22 pmFollowed by: 5 members

Re: If two elements are dropped from set \(X =\{-10, -8, 0, 6, 7\},\) what will be the percentage change in its mean?

by deloitte247 » Thu Nov 12, 2020 10:13 pm
$$X=\left\{-10,\ -8,\ 0,\ 6,\ 7\right\}$$
Mean = -1
Median = 0
Range = 17
Statement 1: The median of the set will remain the same.
x can either be {-10, 0, 6} or {-8, 0, 6} and the mean will either be -1.3 or -0.67. So, there will be a different percentage change in its mean. Statement 1 does not give a definite answer. Hence, it is NOT SUFFICIENT.

Statement 2: The range of the set will decrease by 3
New range = 17 - 3 = 14
From the given set, the range will be 14 if smallest term = -8 and the greatest term = 6
6 - (-8) = 6 + 8 = 14
So, the new set is {-8, 0, 6}; new mean = -0.67
$$\%\ change\ in\ mean=\frac{-0.67+1}{-1}\cdot\frac{100}{1}=\frac{0.33}{-1}\cdot100$$
$$\%\ change\ in\ mean=-33\%$$
Statement 2 alone is SUFFICIENT; answer = option B.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1