import std.stdio, std.string, std.conv, std.algorithm, std.numeric;
import std.range, std.array, std.math, std.typecons, std.container, core.bitop;

void main() {
    while (true) {
        int n, m, p;
        scan(n, m, p);

        if (!n && !m && !p) return;

        auto x = iota(n).map!(i => readln.chomp.to!int).array;
        solve(n, m, p, x).writeln;
    }
}

int solve(int n, int m, int p, int[] x) {
    return x[m-1] == 0 ? 0 : x.sum * (100 - p) / x[m-1];
}


void scan(T...)(ref T args) {
    string[] line = readln.split;
    foreach (ref arg; args) {
        arg = line.front.to!(typeof(arg));
        line.popFront();
    }
    assert(line.empty);
}



void fillAll(R, T)(ref R arr, T value) {
    static if (is(typeof(arr[] = value))) {
        arr[] = value;
    }
    else {
        foreach (ref e; arr) {
            fillAll(e, value);
        }
    }
}