#include <bits/stdc++.h>
using namespace std;
const int maxn = 2020;
double d[maxn][maxn], n, p, t;
int main() {
  cin >> n >> p >> t;
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= t; j++)
      d[i][j] = p * (d[i - 1][j - 1] + 1) + (1 - p) * (d[i][j - 1]);
  cout << fixed << setprecision(10) << d[(int)n][(int)t];
  return 0;
}
