#include <bits/stdc++.h>
using namespace std;
const int inf = 1e9 + 5;
const long long linf = 1e18 + 5;
const int N = 2000 + 5;
int n, t;
bool is[N][N];
double dp[N][N];
double p;
double f(int x, int k) {
  if (x > n) return 0;
  if (k == t) return x == n;
  double &r = dp[x][k];
  if (is[x][k]) return r;
  is[x][k] = 1;
  return r = f(x, k + 1) * (1 - p * !!x) + f(x + 1, k + 1) * p;
}
int main() {
  ios ::sync_with_stdio(0);
  cin >> n >> p >> t;
  double ans = 0;
  for (int i = 0; i <= n; i++) ans += f(n - i, 0) * i;
  cout << fixed << setprecision(12) << ans << '\n';
  return 0;
}
