BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

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.

★★★★★5.0559 reviews
GMATLiveTeach 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
Live EA class + 6 months of EA OnDemand
  • Expert-led weekly online sessions
  • EA Masterclass access between classes
View EA class & enroll
Limited cohort · enrollment openTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

130-point score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 559 reviewsTarget Test Prep

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

Function Q

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 15
Joined: Wed May 21, 2008 6:55 am
by imadummy » Thu Jul 31, 2008 9:15 am
The function F is defined for all positive integers N by the following rule: F(N) is the number of positive integers each of which is less than N and has no positive factor in common with N other than 1. If P is any prime number the F(P)= what?

The answer is P-1...help?!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
GMAT Instructor
Posts: 85
Joined: Thu May 01, 2008 12:56 pm
Location: Salt Lake City, UT
Thanked: 24 times
GMAT Score:750+

by VP_RedSoxFan » Thu Jul 31, 2008 9:17 am
The best way to handle a problem like this, I think, is to do a quick example to understand the function F. F(8) = 4 {7,5,3,1}.

Therefore, pick any prime, say 11. F(11) = 10 {10, 9,8,7,6,5,4,3,2,1} which makes sense because the prime number, by definition, doesn't share any positive common factors with any other number.

So, F(P) = P-1 when P is a prime
Ryan S.
| GMAT Instructor |
Elite GMAT Preparation and Admissions Consulting
www.VeritasPrep.com

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