#include<stdio.h>
int main()
{
    int n;
    scanf("%d" 
    if(n<=0)
    {
        printf("No readings provided");
        return 0;
    }
    int temp;
    float sum=0;
    for(int i=0;i<n;i++)
    {
        scanf("%d" , & temp);
        sum += temp;
    }
    float avg=sum / n;
    printf("%0.2f" , avg);
    return 0;
}