Code:

#include <stdio.h>
#include <math.h>
#define N 400
int main()
{
float array[N]={ 1.8, 4.3, 15.6, 0.2, 10.7, 1.2, 0.9, 5.0, 4.6, 6.8, 4.6,0.7, 5.2,
5.5, 4.5, 5.5, 3.8, 6.8, 5.0, 1.2, 2.0, 1.1, 5.0, 3.3, 2.1, 10.9, 1.4, 1.3,
0.1, 5.0, 2.6, 1.5, 10.3, 23.9, 1.3, 1.8, 1.8, 7.1, 3.6, 9.5, 9.2, 16.1,
15.0, 0.7, 10.0, 5.9, 1.6, 2.8, 2.7, 0.8, 0.2, 6.5, 7.4, 5.2, 0.6, 2.7,
14.8, 6.8, 9.8, 14.9, 5.1, 0.9, 1.3, 4.2, 3.5, 2.2, 1.2, 6.8, 9.0, 8.9, 5.7,
11.5, 1.6, 13.2, 1.1, 3.3, 4.7, 9.9, 1.5, 9.3, 2.6, 8.5, 13.0, 8.2, 1.5};
int i;
float *a;
a = &array[0];
float sum=0.0, average, var=0.0, sd;
printf("Average= %f Variance=%f S.D.=%f\n", average, var, sd);
return 0;
}
float average (int *(a+i), int N)
{
int i;
float sum = 0.0;
for (i=0;i<N;i++)
sum = sum + *(a+i);
return (sum / N);
}
float var(int *(a+1), float average )
{
int i;
float sd;
for (i=0;i<N;i++)
var = var + pow( *(a+i) - average, 2);
sd = sqrt((var)/(N - 1.0));
return (sd);
}

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