#include <bits/stdc++.h>
using namespace std;
int n, t;
double p;
double d[2020][2020];
int main() {
  cin >> n >> p >> t;
  for (int i = 0; i <= n; i++) {
    d[i][0] = 0;
  }
  for (int j = 0; j <= t; j++) {
    d[0][j] = 0;
  }
  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 << setprecision(7) << d[n][t];
  return 0;
}
