diff --git a/module2/exo2/exercice.ipynb b/module2/exo2/exercice.ipynb
index 8141b731fc7e4e7d12eafee288aa6595990a3f2e..f0cddd8717a1106d0d09204f245bd39a496d063a 100644
--- a/module2/exo2/exercice.ipynb
+++ b/module2/exo2/exercice.ipynb
@@ -77,27 +77,27 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 7,
+   "execution_count": 10,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "4.312369534258399"
+       "4.334094455301447"
       ]
      },
-     "execution_count": 7,
+     "execution_count": 10,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "np.std(a)"
+    "np.std(a,ddof=1)"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 8,
+   "execution_count": 11,
    "metadata": {},
    "outputs": [
     {
@@ -106,7 +106,7 @@
        "2.8"
       ]
      },
-     "execution_count": 8,
+     "execution_count": 11,
      "metadata": {},
      "output_type": "execute_result"
     }