diff --git a/chapter_00_intro/00_content.ipynb b/chapter_00_intro/00_content.ipynb
index bbc1dce..0d52716 100644
--- a/chapter_00_intro/00_content.ipynb
+++ b/chapter_00_intro/00_content.ipynb
@@ -220,26 +220,45 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 1,
    "metadata": {
     "slideshow": {
      "slide_type": "slide"
     }
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "3"
+      ]
+     },
+     "execution_count": 1,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "1 + 2"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 2,
    "metadata": {
     "slideshow": {
      "slide_type": "fragment"
     }
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Hello World\n"
+     ]
+    }
+   ],
    "source": [
     "print(\"Hello World\")"
    ]
@@ -267,7 +286,15 @@
      "slide_type": "skip"
     }
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Python 3.8.6\n"
+     ]
+    }
+   ],
    "source": [
     "!python --version"
    ]