C++ Counting average from random numbers from 0 to 1

I finally got code that's giving me random floats from 0 to 1. My code looks like this:

#include<stdio.h>
#include<stdlib.h>
#include<time.h>

int main()
{
srand((int)time(NULL));

int N=10;

float a = 1.0;
for (int i=0;i<N;i++)
    printf("%f\n", ((float)rand()/(float)(RAND_MAX)) * a);

return 0;
}

Now, I need to make program that will give me the average from given numbers for 10<=N<=10000, but im out of ideas how to make it works. Any ideas?