The function F is defined for all positive integers n by the following rule: f(n) is the number of position integer each of which is less than n, and has no position factor in common with n other than 1. If p is any prime number then f(p)=
Choices
A) p-1	B) p-2	C) (p+1)/2	D) (p-1)/2	E) 2
Well as p is a prime, all positive numbers less than p have no common factors with p (except common factor 1). So there would be p-1 such numbers (as we are looking number of integers less than p).   If we consider p=7 how many numbers are less than 7 having no common factors with 7: 1, 2, 3, 4, 5, 6 --&gt; 7-1=6.   p-1nswer: p-1.
<result>A</result>
The function F is defined for all positive integers n by the following rule: f(n) is the number of position integer each of which is less than n, and has no position factor in common with n other than 1. If p is any prime number then f(p)=