#include<bits/stdc++.h>
#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
#define ll long long
#define INF  0x7fffffff//ffffffff
#define dd double
using namespace std;

int main() {
	dd n, m, k;
	while (cin >> n >> m >> k) {
		dd sum = 0;
		dd p = n;
		while (n <= (k + 0.5)) {
			sum += m;
			n += p;
		}
		cout << sum << endl;
	}
}