diff --git a/exam/ex.tex b/exam/ex.tex
index 997ee10..c450e39 100644
--- a/exam/ex.tex
+++ b/exam/ex.tex
@@ -158,7 +158,13 @@
     \item The chaining value size is $\unit[101]{bits}$ ($=g$) and the message
       block size is $655-101=\unit[554]{bits}$.
 
-    \item \TODO
+    \item If the message is of size $|M|=\unit[1234567]{bits}$ and the block
+      size is $\unit[554]{bits}$, we need $\frac{1234866}{554}=2229$ blocks with
+      a padding of $1234866-1234567=\unit[299]{bits}$. Additionally, the
+      message length is also encoded in a $\unit[554]{bit}$ block and so the
+      total number of blocks is $2230$. The total number of blocks corresponds
+      to the total number of evaluations needed, which is $2230$ evaluations of
+      $P$.
 
     \item \TODO