Minor wording change

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@9220 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

prologue/why.xml

@@ -169,8 +169,8 @@
       <listitem>
         <para>GMP</para>
 
-        <para>This package contains math libraries that have useful functions for
-        arbitrary precision arithmetic.  It is required to build Gcc. </para>
+        <para>This package contains math libraries that provide useful functions
+        for arbitrary precision arithmetic.  It is required to build Gcc.</para>
       </listitem>
 
       <listitem>