import java.util.*;
import java.math.*;

public class pre {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
		int n = s.nextInt();
		int member[] = new int[n],sum = 0,deposit = 0;
		
		for(int i=0;i<n;i++){
			member[i] = s.nextInt();
			sum += member[i];
		}
		
		for(int i=0;i<n;i++){
			if(member[i] <= sum/n)
				deposit += 30;
		}
		
		System.out.println(deposit);
    }
}