int[][] scores = {

                { 82, 90, 91 },

                { 68, 72, 64 },

                { 95, 91, 89 },

                { 67, 52, 60 },

                { 79, 81, 85 },

        };

        // TODO:

        double average = 0;

        int count = 0;

        double sum = 0;

        for (int ns[]: scores){

            for (double n: ns){

                count ++;

                sum += n;

            }

        }

        average  = sum / count;

        System.out.println(average);