diff --git a/ejercicios_hilos/ej03.py b/ejercicios_hilos/ej03.py
new file mode 100644
index 0000000..df6cff7
--- /dev/null
+++ b/ejercicios_hilos/ej03.py
@@ -0,0 +1,38 @@
+import threading
+import time
+import random
+
+def tareaUno():
+  global Done
+  time.sleep (random.random())
+  if not Done:
+    print("Tarea realizada")
+    time.sleep(0.1)
+    Done = True
+  else :
+    print ("tarea NO REALIZADA")
+    time.sleep(0.01)
+  return
+
+def tareaDos():
+  global Done
+  Done = False
+  print("Desactivo")
+
+hilos1 = list()
+for i in range(50):
+  t = threading.Thread(target=tareaUno)
+  hilos1.append(t)
+  t.start()
+
+Done = False
+tareaUno()
+
+hilos2 = list()
+for i in range(5):
+  t2 = threading.Thread(target=tareaDos)
+  hilos2.append(t2)
+  t2.start()
+  time.sleep(1)
+  
+time.sleep(6)
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