Class average, rounded to the nearest integer on each problem was
as shown in the first column of this table:

Problem\        max

penalty  0        0
1       25       30
2       21       30
3       22       40
4       11       20
Total   79      120

Here is the distribution of all 34 grades, in order:

120 119 119 113 111 110 110 110 110 109 107 106  98  94  92  89  82 
 82  75  74  74  68  67  63  56  50  50  45  44  43  35  34  18  13