quiz grades for groupA                          avg
5169-644 18 13  0  0  0  0                       7.75
4796-425 19 20 16 12 10 12                      16.75
8608-181  8  5 16  7 10  2                      10.25
3853-674 18 20 14 12 17 17                      18.00
1720-017 19  9 15 12 12  5                      14.50
2766-905 16 10  8  7  5  4                      10.25
9390-030 16 13  9  8 14 13                      14.00
9665-282 13 15  7 18 19 20                      18.00
1996-615 15 17  6 17 11  8                      15.00
5906-414 20 14 14  8 13  0                      15.25
4219-155  0  0  0  0  0  0                       0.00
4567-388 18 17 10 10 19 14                      17.00
0137-597 15  5 18 16 14  0                      15.75
1009-615  5  0 13 12  3  6                       9.00
9023-721 17  0  5  0  0  0                       5.50
5779-440 18 20 20 13 20 17                      19.50
6754-703 20 20 20 15 20  0                      20.00
4402-976  5  4  8  0  0  0                       4.25
2918-601 20  0 10 17 20  3                      16.75
2364-669 14  7  9  6 16  0                      11.50
the average was computed with  2 drops