#include <bits/stdc++.h>
using namespace std;
const long long infi = 1000000000000000009;
double dp[2009][2009];
double p;
int n, t;
double doit(int i, int d) {
  if (i == 0) return n;
  if (d == 0) return n - i;
  double ans = 0.0;
  if (dp[i][d] > (-0.5)) return dp[i][d];
  ans += p * doit(i - 1, d - 1);
  ans += (1 - p) * doit(i, d - 1);
  return dp[i][d] = ans;
}
int main() {
  scanf("%d%lf%d", &n, &p, &t);
  int i, j;
  for (i = 0; i <= 2004; i++)
    for (j = 0; j <= 2004; j++) dp[i][j] = -1.0;
  double an = doit(n, t);
  printf("%0.9lf\n", an);
  return 0;
}
