diff --git a/03_classification.ipynb b/03_classification.ipynb
index 0e7545d..0717be2 100644
--- a/03_classification.ipynb
+++ b/03_classification.ipynb
@@ -484,14 +484,20 @@
     "    plt.grid(True)                              # Not shown\n",
     "    plt.axis([-50000, 50000, 0, 1])             # Not shown\n",
     "\n",
-    "plt.figure(figsize=(8, 4))                      # Not shown\n",
+    "\n",
+    "\n",
+    "recall_90_precision = recalls[np.argmax(precisions >= 0.90)]\n",
+    "threshold_90_precision = thresholds[np.argmax(precisions >= 0.90)]\n",
+    "\n",
+    "\n",
+    "plt.figure(figsize=(8, 4))                                                                  # Not shown\n",
     "plot_precision_recall_vs_threshold(precisions, recalls, thresholds)\n",
-    "plt.plot([7813, 7813], [0., 0.9], \"r:\")         # Not shown\n",
-    "plt.plot([-50000, 7813], [0.9, 0.9], \"r:\")      # Not shown\n",
-    "plt.plot([-50000, 7813], [0.4368, 0.4368], \"r:\")# Not shown\n",
-    "plt.plot([7813], [0.9], \"ro\")                   # Not shown\n",
-    "plt.plot([7813], [0.4368], \"ro\")                # Not shown\n",
-    "save_fig(\"precision_recall_vs_threshold_plot\")  # Not shown\n",
+    "plt.plot([threshold_90_precision, threshold_90_precision], [0., 0.9], \"r:\")                 # Not shown\n",
+    "plt.plot([-50000, threshold_90_precision], [0.9, 0.9], \"r:\")                                # Not shown\n",
+    "plt.plot([-50000, threshold_90_precision], [recall_90_precision, recall_90_precision], \"r:\")# Not shown\n",
+    "plt.plot([threshold_90_precision], [0.9], \"ro\")                                             # Not shown\n",
+    "plt.plot([threshold_90_precision], [recall_90_precision], \"ro\")                             # Not shown\n",
+    "save_fig(\"precision_recall_vs_threshold_plot\")                                              # Not shown\n",
     "plt.show()"
    ]
   },