Question
If p and q are different primes (so each > or = 2) and if n= pq, then the number of integers of the set 2, 3, 4,..., n which have no common factors (other than 1) in with n is
A. n-pq
B. pq-(p+q)
C. pq-(p+q+1)
D. pq-3
E. pq-4
A. n-pq
B. pq-(p+q)
C. pq-(p+q+1)
D. pq-3
E. pq-4