added solutions 4 and 5

problem5.py

@@ -0,0 +1,16 @@
+done = False
+key = 1
+
+def modulo(n):
+  for i in range(1,21):
+    if n % i != 0:
+      return False
+  return True
+
+while not done:
+  num = key*20
+  done = modulo(num)
+
+  key += 1
+
+print(num)