corrected a typo that prevented compilation on OSX

source/db2-presentation.tex

@@ -258,7 +258,7 @@ The authors utilized two types of benchmarks:
   \begin{itemize}
     \item Read-heavy: 90\% reads and \% updates.
     \item Write-heavy: 50\% reads and 50\% writes.
-    \item Read-only: 100\5 reads.
+    \item Read-only: 100\% reads.
   \end{itemize}
   \item \textbf{Multi-step read/update workload} (1GB single-table database, 56 bytes records) that is divided in:
   \begin{itemize}