--- a/faq/index.php
+++ b/faq/index.php
@@ -300,6 +300,19 @@
 </em></blockquote>
 </p>
 
-
+<h3>Why doesn't the summary sample count for some binary images match the number of individual symbols'
+samples for the same binary?</h3>
+<p>
+Usually, the total of all per-symbols samples for a given binary image
+equals the summary count for the binary image (shown by running
+opreport with no options).
+However, it's possible for some sample addresses to fall outside the range of
+any symbols for a given binary image.  In such cases, the total number of
+per-symbols samples for the binary image may be less than the summary count
+for the image. Running opreport with the <tt>--verbose=debug</tt> option
+will display an informational message when this difference is detected.
+This difference is typically very small and can be ignored.
+
+</p>
 
 <?php require("$top/end_page.php"); end_page("faq/"); ?>