#!/usr/bin/env python
N = 10
sum = 0
count = 0
while count < N:
    number = float(raw_input(""))
    sum = sum + number
    count = count + 1
average = float(sum)/N
print "N = %d , Sum = %f" % (N, sum)
print "Average = %f" % average

[kd@kdlappy book]$ ./averagen.py
1
2.3
4.67
1.42
7
3.67
4.08
2.2
4.25
8.21
N = 10 , Sum = 38.800000
Average = 3.880000