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 →

DIGITS ISSUE

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 124
Joined: Sun Mar 07, 2010 3:15 pm
Thanked: 1 times
by francoisph » Wed Jun 16, 2010 4:17 am
Hi,

please any ideas?

if a two digits positive integer has its digits reversed, the resulting integer differs from the original by 27.
By how much do the two digits differ?


thks,
francois
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 1460
Joined: Tue Dec 29, 2009 1:28 amFollowed by: 7 members
Thanked: 135 times

by selango » Wed Jun 16, 2010 4:18 am
10x+y=10y+x+27

9x-9y=27

-->x-y=3
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 294
Joined: Wed May 05, 2010 4:01 am
Location: india
Thanked: 57 times

by amising6 » Wed Jun 16, 2010 4:31 am
if a two digits positive integer has its digits reversed, the resulting integer differs from the original by 27.
By how much do the two digits differ?


let two digit be xy = 10x+y (since has is at 10 th place)
reversing digit we have xy=10 y+x
(10x+y)-(10y-x)=27
9x-9y=27 dividing by 9 both side
x-y=3
so fdifference between two digit =3
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 124
Joined: Sun Mar 07, 2010 3:15 pm
Thanked: 1 times

by francoisph » Wed Jun 16, 2010 4:35 am
why ? xy = 10x+y (since has is at 10 th place)

where 10X comes from please?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 294
Joined: Wed May 05, 2010 4:01 am
Location: india
Thanked: 57 times

by amising6 » Wed Jun 16, 2010 4:42 am
dude lets us take no 12
12 can also be written as 10.1 +2
so i have taken 2 digit as number as xy whixh is equal to 10x+y
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 1460
Joined: Tue Dec 29, 2009 1:28 amFollowed by: 7 members
Thanked: 135 times

by selango » Wed Jun 16, 2010 4:43 am
If 2 digit number can be expressed as xy,Tenth digit will be x and expressed as 10x

for ex 75,x=5,y=5 will be 10(7)+5
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 124
Joined: Sun Mar 07, 2010 3:15 pm
Thanked: 1 times

by francoisph » Wed Jun 16, 2010 4:59 am
ok guys

thks
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1