№3.
for i in range(100, 999 + 1):
if(i % 15 == 11 and i % 11 == 9):
print(i)
№4.
x = int(input())
n = 0
for i in range(2, x):
if(x % i == 0):
n += 1
break
if(n == 1):
print("Не простое")
else:
print("Простое")
