import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int[] c = new int[n];
		for(int i = 0 ; i < n ; i++) c[i] = sc.nextInt();
		int total = 0;
		for(int i = 0 ; i < n ; i++) {
			total += c[i];
		}
		double avg = 1.0 * total / 10;
		int ans = 0;
		for(int i = 0 ; i < n ; i++) {
			if(avg >= c[i]) {
				ans += 30;
			}
		}
		System.out.println(ans);
 	}
}