diff --git a/is/UB1/ISUB1.pdf b/is/UB1/ISUB1.pdf
index a7117b9..341cce9 100644
--- a/is/UB1/ISUB1.pdf
+++ b/is/UB1/ISUB1.pdf
Binary files differ
diff --git a/is/UB1/ISUB1.tex b/is/UB1/ISUB1.tex
index e0a6a4c..a3e69b8 100644
--- a/is/UB1/ISUB1.tex
+++ b/is/UB1/ISUB1.tex
@@ -69,7 +69,7 @@
 %Kommando für Aufgaben
 %\Aufgabe{AufgTitel}{Punktezahl}
 \newcommand{\Aufgabe}[2]{\stepcounter{n}
-    \indent\textbf{Exercise \arabic{n}: #1} (#2 Punkte)\\}
+    \indent\textbf{Exercise \arabic{n}: #1} (#2 Points)\\}
 
 
 
@@ -90,7 +90,10 @@
             $\mathds{P}(2\ pairs)=\frac{123552}{2598960}=\frac{198}{4165}\approx 0.0475$
             \item \begin{enumerate}[(a)]
                 \item hands with exaclty two pairs without Spades: ${13\choose 2}{3\choose 2}^2\cdot 11\cdot 3=23166$\\
-                $\mathds{P}(2\ pairs|\neg Spades)=\frac{23166}{2598960}=\frac{297}{33320}\approx 0.00891$
+                $\mathds{P}(2\ pairs|\neg Spades)=\frac{23166}{2598960}=\frac{297}{33320}\approx 0.00891$\\
+                one pair:\\
+                ${13\choose 1}{3\choose 2}{12 \choose 3}\cdot 3^3=231660$\\
+                $\mathds{P}(1\ pair|\neg Spades)=\frac{231660}{2598960}=\frac{297}{3332}\approx 0.0891$
                 \item $A:=2\ pairs,\ B:=\neg Spades$\\
                 $P(A|B)=\frac{P(B|A)P(A)}{P(B)}$\\
                 $P(A)=\frac{198}{4165},\ P(B)=\frac{39}{52}\cdot\frac{38}{51}\cdot\frac{37}{50}\cdot\frac{36}{49}\cdot\frac{35}{48}=\frac{2109}{9520}$\\
@@ -108,6 +111,8 @@
                 1 & if\ x>\sqrt{2}
             \end{cases}$
         \end{enumerate}
-
+    \Aufgabe{Keep Rolling!}{4}
+        $\mathds{E}(X)=\frac{1}{\frac{1}{6}}=6$ (geometric distribution)\\
+        $\mathds{E}(X)=?$%TODO
 \end{document}