diff --git a/practical5.ipynb b/practical5.ipynb
index 22391e9..481a665 100644
--- a/practical5.ipynb
+++ b/practical5.ipynb
@@ -125,7 +125,7 @@
         "\"Evidence? Of what?,\" you might ask. Bayes's theorem states that\n",
         "\n",
         "\\begin{align}\n",
-        "p_{\\theta}(z|x) & = \\frac{p_{\\theta}(z|x) \\, p(z)}{p_{\\theta}(x)} \\\\\n",
+        "p_{\\theta}(z|x) & = \\frac{p_{\\theta}(x|z) \\, p(z)}{p_{\\theta}(x)} \\\\\n",
         "\\textrm{posterior} & = \\frac{\\textrm{likelihood} \\times \\textrm{prior}}{\\textrm{evidence (or marginal likelihood)}}\n",
         "\\end{align}\n",
         "\n",