diff --git a/renderer.php b/renderer.php
index b3ebaac6..298440bf 100644
--- a/renderer.php
+++ b/renderer.php
@@ -854,7 +854,7 @@ public function part_correct_response($part) {
         return html_writer::nonempty_tag(
             'div',
             get_string($string, 'qtype_formulas', $answertext),
-            ['class' => 'formulaspartcorrectanswer'],
+            ['class' => 'formulaspartcorrectanswer filter_mathjaxloader_equation'],
         );
     }