Answer:
A=input("Enter Number of Marks:")
b=[]
sum=0
i=0
for i in range(0,int(A)):
b.append(input("Enter Marks"))
sum+=int(b[i])
percentage1= (sum/int(A))*100
if percentage1>=20:
print("Grade A")
elif percentage1<=30 & percentage1>=20:
print("Grade B")
else:
print("Grade C")
Step-by-step explanation:
The above program is in Python. And we are using here a dynamic list. And we are storing A marks in it. And then we are finding its average, and finally assigning the Grade as mentioned.