diff --git a/ex04/kn04.pdf b/ex04/kn04.pdf
index 18ba791..9a54372 100644
--- a/ex04/kn04.pdf
+++ b/ex04/kn04.pdf
Binary files differ
diff --git a/ex04/kn04.tex b/ex04/kn04.tex
index 76a9fd7..7561e11 100644
--- a/ex04/kn04.tex
+++ b/ex04/kn04.tex
@@ -127,10 +127,10 @@
   \begin{align*}
     B_{PCM} = c \cdot 2 \cdot B_{analog} \cdot n_{b} \cdot \frac{1}{r}
   \end{align*}
-  where $c$ is the average probability, that the next bit changes ($c = 0.5$), $r$ is the number of data per signal (here $r = 2$).
+  where $c$ is the average probability, that the next bit changes ($c = 0.5$), $r$ is the number of data per signal (here $r = 2$)\begin{corr}$r=4$\end{corr}).
   Therefore the required bandwidth is:
   \begin{align*}
-      B = 0.5 \cdot 8000Hz \cdot 8bit \cdot \frac{1}{2} = 16kHz
+      B = 0.5 \cdot 8000Hz \cdot 8bit \cdot \frac{1}{\begin{corr}4\end{corr}} = \begin{corr}8\end{corr}kHz
   \end{align*}
 \end{enumerate}
 \Aufgabe{Modulation}{10+10+10}
@@ -151,4 +151,5 @@
       \includegraphics[width=\linewidth]{BPSK.png}
   \end{minipage}
 \end{enumerate}
+\begin{corr}tables missing\end{corr}
 \end{document}