Averaging Paramaeters

I have com-sci homework
The java code is :
public class DemoAverage{

public static void main(String[] args){
int t1 = 90, t2=85, t3=70, t4=89, t5 = 88, t6 = 100, t7 = 65, t8=76;

System.out.println("*****Welcome to my average machine*****");
System.out.println(" Demonstrating averages\n");
System.out.println("The average of " + t1+ " and " + t2 + " is "+average(t1,t2));
System.out.println("The average of " + t5+ ", "+t3 +" and " + t7 + " is "+average(t5,t3, t7));
double ave1 = average(t8,t3,t4,t1,t5);
System.out.println("The average of " + t8+ ", "+t3 +", "+t3 + ", "+t4 + " and " + t1 +
" is " +ave1);
double ave2 = average(t1,t3,t5,t7);
System.out.println("The average of " + t1+ ", "+t3 + ", "+t5 + " and " + t7 + " is " +ave2);
double ave3 = average(t2,t4,t6,t8);
System.out.println("The average of " + t2+ ", "+t4 + ", "+t6 + " and " + t8 + " is " +ave3);
averageAverages(ave1, ave2, ave3);
System.out.println("The End");
}

public static double average(int a,int b) {
return (a + b) / 2.0;
}

public static double average(int a,int b, int c) {
return (a + b + c) / 3.0;
}
public static double average(int a,int b, int c, int d) {
return (a + b + c + d) / 4.0;
}
public static double average(int a,int b, int c, int d, int e) {
return (a + b +c + d + e) / 5.0;
}
public static double average(double a,double b, double c) {
return (a + b + c) / 3.0;
}

public static void averageAverages(double a1, double a2, double a3){
double aa = average(a1, a2, a3);
System.out.println("The averages of the averages " + a1 + ", "+a2 +" and "+a3+" are " +aa);
}
}
QUESTION
14. Add a method to your program to average 2 averages

public static void averageAverages(double a, double b)



15. Add a statement to the main method to call your new method.


16. Final List:



17. Final run:

I get error after error and I don't know what to do.
PLEASE give clear explanations like you're talking to a child probably

problems start when I try to write the statement to the main method. do I write the statement under the public static void main (String[] args){
or
as a seperate one like public static void averageAverages
?

Sorry if I'm unclear I'm just very stressed out with this...