924extra1.c

#include <stdio.h>
int main(){
  int i;
  float x,n;
  float sum_x = 0.0;
  float squared_x = 0.0;
  float mean,variance;
  printf("n = "); 
  scanf("%f", &n);
  for(i=1;i<=n;i++){
    printf("x = ");
    scanf("%f",&x);
    sum_x += x;
    squared_x += x*x;
  }
  mean = sum_x/n;
  variance = (squared_x/n)-mean*mean;
  printf("mean is %f\n",mean);
  printf("variance is %f\n",variance);
  return 0;
}