diff --git a/Rethinking_2/Chp_02.ipynb b/Rethinking_2/Chp_02.ipynb
index 0a87846..3843103 100644
--- a/Rethinking_2/Chp_02.ipynb
+++ b/Rethinking_2/Chp_02.ipynb
@@ -116,7 +116,7 @@
     "    unstd_posterior = likelihood * prior\n",
     "\n",
     "    # standardize the posterior, so it sums to 1\n",
-    "    posterior = unstd_posterior / unstd_posterior.sum()\n",
+    "    posterior = unstd_posterior / (unstd_posterior.sum()/grid_points)\n",
     "    return p_grid, posterior"
    ]
   },