#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2020;
int n, t;
double p, d[MAXN][MAXN];
int main() {
  scanf("%d%lf%d", &n, &p, &t);
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= t; j++)
      d[i][j] = (1 - p) * d[i][j - 1] + p * (d[i - 1][j - 1] + 1);
  printf("%.10lf\n", d[n][t]);
}
