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 →

Permutation

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |
Legendary Member
Posts: 752
Joined: Sun May 17, 2009 11:04 pm
Location: Tokyo
Thanked: 81 times
GMAT Score:680

by tohellandback » Wed Jul 22, 2009 4:15 am
from the image,
4+y=-5
y=-9

4+x=1
x=-3

e+x=7
or,e+(-3)=7
e=10

e+z=10
z=10-e=10=10=0

n=e+y
=10-9=1

m=4+z=4+0=4

so m+n=4+1=5
The powers of two are bloody impolite!!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 379
Joined: Wed Jun 03, 2009 3:05 amFollowed by: 1 member
Thanked: 19 times
GMAT Score:690

by sreak1089 » Wed Jul 22, 2009 4:49 am
You can have one-letter, two-letter and three-letter codes:

1) one-letter codes: 26 possibilities
2) two-letter codes: 26 * 26 possibilities (since repetion is allowed)
3) three-letter codes: 26 * 26 * 26 possibilities

Total no of possibilities = 26 + 26 * 26 + 26 * 26 * 26 = 18278
Hence answer is E
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 157
Joined: Tue Oct 07, 2008 5:47 am
Thanked: 3 times

by PussInBoots » Sat Jul 25, 2009 5:16 pm
Would not it take a significant time to calculate 26 + 26^2 + 26^3?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 113
Joined: Thu Jul 16, 2009 11:23 am
Thanked: 15 times
GMAT Score:730

by prindaroy » Sat Jul 25, 2009 7:34 pm
well the only calculation you would actually have to do is 26^3. 26^2 is simply 625 + 25 + 26 = 676. If you remember that 25^2 = 625. Also, 625 * 26 should take less than a minute for sure.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 379
Joined: Wed Jun 03, 2009 3:05 amFollowed by: 1 member
Thanked: 19 times
GMAT Score:690

by sreak1089 » Sat Jul 25, 2009 8:04 pm
Only calculation you have to do is 676 * 26. It helps if you remember squares of numbers up to 35.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1