#include <bits/stdc++.h>
double a[10000];
double b[2][10000];
int cmp(void const* a, void const* b) {
  double a1 = *(double*)a;
  double b1 = *(double*)b;
  if (a1 > b1)
    return 1;
  else if (a1 < b1)
    return -1;
  return 0;
}
int main() {
  double q0, q1, q, k;
  int N, i, j, n = 0;
  scanf("%d", &N);
  scanf("%lf", &k);
  for (i = 0; i < N; i++) scanf("%lf", &a[i]);
  qsort(a, N, sizeof(double), cmp);
  for (i = 0; i < N; i++) {
    q0 = q1 = 0;
    q = a[i];
    for (j = 0; j < N; j++) {
      if (a[j] > q)
        q1 = q1 + (a[j] - q);
      else if (a[j] < q)
        q0 = q0 + (q - a[j]);
    }
    b[0][i] = q0;
    b[1][i] = q1;
  }
  for (i = 1; i < N; i++) {
    q1 = b[0][i] / b[1][i];
    q0 = b[0][i - 1] / b[1][i - 1];
    if (q0 <= 1 - (k / 100) && q1 >= 1 - (k / 100)) {
      for (j = i; j < N; j++) {
        if (a[j] > a[i - 1]) n++;
      }
      q = ((1 - k / 100) * b[1][i - 1] - b[0][i - 1]) / (N - n * k / 100) +
          a[i - 1];
      break;
    }
  }
  printf("%.9lf", q);
}
