# program to calculate average of class marks
mark = [[10,10,10],
        [7,6,9],
        [0,0,5],
        [0,0,0],
        [2,2,2]]
classTotal = 0
for s in range(5):
    stotal=0
    for m in range(3):
        stotal = stotal + mark[s][m]
    if stotal>0:
        studentAverage = round(stotal/3,1)
    else:
        studentAverage = 0
    print("Average mark for student ",s, "is ",studentAverage)
    classTotal = classTotal +stotal
classAvg =classTotal/15
print("Class average = ",classAvg)