#include <stdio.h>

int main(){
  
  int N,M,P,X[1000],Xsum,kake,win,i;
  
  kake=0;
  Xsum=0;
  win=0;
  while(1){
    scanf("%d%d%d",&N,&M,&P);
    if(N==0 && M==0 &&P==0)break;
    for(i=0;i<N;i++)X[i]=0;
    for(i=1;i<=N;i++){
      scanf("%d",&X[i]);
      Xsum += X[i];
      if(M==i)win=X[i];
    }
    if(win==0)printf("0\n");
    else{ kake=(Xsum*100-(Xsum*100*P/100))/win;
      printf("%d\n",kake);
    }
    Xsum=0;
  }
  return 0;
}