#include <stdio.h>

int main() {
    int n = 0;
    scanf("%d", &n);
    double sum = 0.0;
    for (int i = 0; i < n; i++) {
        int val = 0;
        scanf("%d", &val);
        if (val > 60) {
            sum += 0.2 ;
        } else {
            sum += 0.1;
        }
    }
    printf("%.1lf", sum);
    return 0;
}