quiz grades for groupB                          avg
3088-893  5  0  0  0                             1.67
5047-380 21  8 14  0                            14.33
9043-561 16 17 20 11                            17.67
9638-260  8  0  0  0                             2.67
6476-708 14 12 14 10                            13.33
3940-305 25 25 23  7                            24.33
1134-229 19 12 19 15                            17.67
9487-123  0  0  0  0                             0.00
4083-503  9 11 17  2                            12.33
8535-040 12 11 12  5                            11.67
2829-859 18 10 11  7                            13.00
7111-305 11  0 11  2                             8.00
2745-511  2  0 12  7                             7.00
5187-483 24  2  0  0                             8.67
6176-439 11  7  3  0                             7.00
4917-370 18 21 16  0                            18.33
4794-145  9 13 13 15                            13.67
3922-170  2 11 14  6                            10.33
the average was computed with  1 drop