#include <bits/stdc++.h>
using namespace std;
using namespace chrono;
#if __has_include(<atcoder/all>)
#include <atcoder/all>
using namespace atcoder;
#endif

int main() {
    long double a, b, c;
    cin >> a >> b >> c;

    cout << fixed << setprecision(20) << (c / b * a) << endl;

    return 0;
}