#include <stdio.h>

void main() {
    int data[4][3] = {
        {81, 90, 62},
        {50, 83, 87},
        {89, 55, 65},
        {77, 70, 92},
    };

    for (int i = 0; i < 4; i++) {
        int total = 0;
        for (int j = 0; j < 3; j++) {
            total += data[i][j];
        }

        printf("%d     %.2f\n", i + 1, (float) total / 3);
    }
}