#include <stdio.h>

int main(){
    int n;
    if(scanf("%d", &n) != 1) return 0;
    int total_usia = 0;
    for (int i = 0; i < n; i++){
        int usia;
        char nama[100];
        scanf("%d;[^\n]", &usia, nama);
        printf("%s\n", nama);
        total_usia += usia;
    }
    if (n > 0){
        double rata_rata = (double)total_usia / n;
        printf("%.2f\n", rata_rata);
    }
    return 0;
}