diff --git a/module2/exo2/exercice.ipynb b/module2/exo2/exercice.ipynb
index ccbde059dfa931d5b19008629818f2de919071b1..37056d6394b488ed99c41e994a11911deea004d9 100644
--- a/module2/exo2/exercice.ipynb
+++ b/module2/exo2/exercice.ipynb
@@ -158,22 +158,22 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 8,
+   "execution_count": 9,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "4.312369534258399"
+       "4.334094455301447"
       ]
      },
-     "execution_count": 8,
+     "execution_count": 9,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "np.std(data)"
+    "np.std(data, ddof=1)"
    ]
   }
  ],