C :

#include<stdio.h>
int main(){
  double x, rate, pay;
  scanf("%lfd", &x);
  if(x < 300){
    rate = 1.0;
  } else if(x < 500){
    rate = 0.9;
  } else if(x < 800){
    rate = 0.7;
  } else {
    rate = 0.5;
  }
  pay = x * rate;
  printf("%.2lf %.2lf", rate, pay);
  return 0;
}

C++ :

#include<stdio.h>   
int main()
{ 
	double x,y;
	scanf("%lf",&x);
if (x < 300.00)
{
    y = x;
	printf("0.00 %.2lf",y);
}
else if (x < 500.00)
{
    y = 0.90 * x;
    printf("0.90 %.2lf",y);
}
else if (x < 800.00)
{
    y = 0.70 * x;
    printf("0.70 %.2lf",y);
}
else 
{
	y = 0.50 * x;
    printf("0.50 %.2lf",y);
}
	return 0;
}

Pascal :

program ex_1;
var
 a:real;
begin
 readln(a);
 if a<300 then writeln('0.00 ',a)
 else if (a>=300) and (a<500) then writeln('0.90 ',a*0.9:0:2)
 else if (a>=500) and (a<800) then writeln('0.70 ',a*0.7:0:2)
 else writeln('0.50 ',a*0.5:0:2);
end.