#include <bits/stdc++.h>
using namespace std;
using ii = pair<long long, long long>;
const long long mn = 2e3 + 11, inf = 0x3f3f3f3f3f3f3f3f;
template <typename t>
bool ckmax(t& target, const t& source) {
  return target < source ? target = source, 1 : 0;
}
template <typename t>
bool ckmin(t& target, const t& source) {
  return target > source ? target = source, 1 : 0;
}
long long n, t;
long double p;
long double dp[mn][mn];
int32_t main() {
  cin.tie(0)->sync_with_stdio(0);
  cin >> n >> p >> t;
  dp[0][0] = 1;
  long double res = 0;
  for (long long i = 1; i <= t; i++) {
    dp[i][0] = dp[i - 1][0] * (1.0L - p);
    long long eval = min(i, n - 1);
    for (long long j = 1; j <= eval; j++)
      dp[i][j] = dp[i - 1][j] * (1.0L - p) + dp[i - 1][j - 1] * p;
    if (i >= n) dp[i][n] = dp[i - 1][n] + dp[i - 1][n - 1] * p;
  }
  for (long long i = 1; i <= n; i++) res += i * dp[t][i];
  cout << setprecision(10) << res;
}
