#include <bits/stdc++.h>
using namespace std;
int n, t;
double f[2010][2010];
double p;
int main() {
  scanf("%d%lf%d", &n, &p, &t);
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= t; j++)
      f[i][j] = (f[i - 1][j - 1] + 1) * p + f[i][j - 1] * (1 - p);
  printf("%lf", f[n][t]);
  return 0;
}
