#include <bits/stdc++.h>
using namespace std;
const int N = 2e3 + 2;
long double dp[N][N], n, t, p;
long double solve(int rt, int rn) {
  if (rt == t || rn == n) return rn;
  long double &ret = dp[rt][rn];
  if (ret == ret) return ret;
  ret = 0;
  if (rn < n) ret = solve(rt + 1, rn + 1) * p;
  ret += solve(rt + 1, rn) * (1.0 - p);
  return ret;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> n >> p >> t;
  memset(dp, -1, sizeof dp);
  cout << fixed << setprecision(7) << solve(0, 0) << endl;
  return 0;
}
