Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 13 Feb 2016, 01:06

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

The function f is defined for all positive integers n by the

Author Message
Manager
Joined: 17 Aug 2006
Posts: 87
Followers: 1

Kudos [?]: 13 [0], given: 0

The function f is defined for all positive integers n by the [#permalink]  13 Nov 2008, 04:19
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

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 an prime number then f(p) =

p-1

p-2

(p+1)/2

(p-1)/2

2
SVP
Joined: 17 Jun 2008
Posts: 1570
Followers: 12

Kudos [?]: 222 [0], given: 0

Re: Prime f(p) [#permalink]  13 Nov 2008, 04:50
p-2.

Since, p is a prime number, the only common factor between p and all positive integers less than p is 1.
Manager
Joined: 08 Aug 2008
Posts: 234
Followers: 1

Kudos [?]: 25 [0], given: 0

Re: Prime f(p) [#permalink]  13 Nov 2008, 10:13
$$P-1.$$

f(p) will be all numbers between 1 and P, inclusive of 1 and excluding P i.e. $$1<=f(p)<P$$
Manager
Joined: 23 Jul 2008
Posts: 203
Followers: 1

Kudos [?]: 63 [0], given: 0

Re: Prime f(p) [#permalink]  13 Nov 2008, 10:30
IMO A
p-1
f(2)=1
f(3)=2
f(5)=4
the only doubt i had with this one is whether to count 1 or not. I believe we should hence A
Manager
Joined: 15 Oct 2008
Posts: 54
Followers: 1

Kudos [?]: 2 [0], given: 0

Re: Prime f(p) [#permalink]  17 Nov 2008, 02:07
IMO A

I include 1 coz : f(n) is the number of positive integers each of which is less than n

what's OA
Re: Prime f(p)   [#permalink] 17 Nov 2008, 02:07
Display posts from previous: Sort by