diff --git a/source/sec-Variance.ptx b/source/sec-Variance.ptx
index 929c8f9..5f37827 100644
--- a/source/sec-Variance.ptx
+++ b/source/sec-Variance.ptx
@@ -283,6 +283,12 @@
           If <m>\E(X) = 3</m>, <m>\Var(X) = 2</m>, what is <m>\E(X^2)</m>?
         </p>
       </statement>
+
+      <answer>
+        <p>
+          <m>11</m>.
+        </p>
+      </answer>
     </exercise>
 
     <exercise>