#include<iostream>
using namespace std;
int main() {
	int n;
	int m;
	int p;
	int answer=0;
	int x[1000];
	while (1) {
		cin >> n;
		cin >> m;
		cin >> p;
		
		if (n == 0 && m == p && p == 0) {
			break;
		}

		for (int i = 0; i < n; i++) {
			cin >> x[i];
			answer += x[i];
		}
		if (x[m - 1 ]!= 0) {
			answer = (answer*(100- p)) / x[m - 1]; 
		}
		else {
			answer = 0;
		}
		cout << answer;

	}
}
