Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 563 reviewsTarget Test Prep

Unable to solve,plz help.

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
User avatar
Legendary Member
Posts: 1132
Joined: Mon Jul 20, 2009 3:38 amFollowed by: 6 members
Location: India
Thanked: 64 times
GMAT Score:760
by harsh.champ » Thu Feb 04, 2010 5:50 am
For a positive integer n, let Pn denote the product of the digits of n, and Sn denote the sum of the digits of n. The number of integers between 10 and 1000 for which Pn + Sn = n is


(1)81
(2)16
(3)18
(4)9
(5)27


_______________________

I am unable to find any method to solve such type of questions?
Is there any formal and proper method/technique ??
Top
Join the discussion
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 1275
Joined: Thu Sep 21, 2006 11:13 pmFollowed by: 2 members
Location: Arabian Sea
Thanked: 125 times

by ajith » Thu Feb 04, 2010 6:06 am
(1)81
(2)16
(3)18
(4)9
(5)27


_______________________

I am unable to find any method to solve such type of questions?
Is there any formal and proper method/technique ??[/quote]


for two digit numbers in the form ab

Pn = ab
Sn = a+b

Pn + Sn = ab+a+b

ab+a+b = 10a+b

ab = 9a

b=9

19 follows the rules
so does 29..39....99

9 numbers in total

For 3 digit numbers
abc

Pn = abc
Sn = a+b+c
abc+a+b+c = 100a+10b+c
abc = 99a+9b
abc = 9(11a+b)

for a =1
bc = 99 +9b {not possible}
for a=2
2bc = 198+b

not possible ...

.
.
.
for a=9
9*bc = 891+ 9b
not possible

So, 9 is the answer
Always borrow money from a pessimist, he doesn't expect to be paid back.
Top
Join the discussion