I can not sort the fix in Java

I can not keep the final grade after the notes as an arrangement, it's supposed to be [4][8] and in [i][7] memorize the final note but this is not the case and indicate it below. Estimated suggestions?

            public static void main (String[] args) {

double[][]    Notes = new double[4][8];
Chain[] a = new chain[4];
Chain[] students = {"Pedro", "Juan", "Diego", "Carlos"};

for (int i = 0; i <notes.length; i ++) {
for (int j = 0; j <7; j ++) {
marks[i][j]    = Math.round (((double) (Math.random () * 6 + 1)) * 10d)
/ 10d;
}
}
for (int i = 0; i <notes.length; i ++) {
System.out.print ("Student notes:" + students[i])
for (int j = 0; j <notes[i]length; j ++) {
System.out.print ("["+Rating["+Notas["+notes["+notas[i][j]    + "]");
} System.out.println ("");
}
double n2 = 0;
double n1 = 0;
for (int i = 0; i <4; i ++) {
n1 = 0;
for (int j = 0; j <4; j ++) {
n1 = n1 + ((notes[i][j]* 0.15) / 4);

} notes[i][7]    = (n1 + (notes[i][4]* 0.20) +
(Notes[i][5]* 0.25) + (notes[i][6]* 0.40));
System.out.println (notes[i][7])
}
}
}