diff --git a/tidyquestionform.php b/tidyquestionform.php
index 26777a4802439478b2ba73cb2423bebcba74a7a7..a45b934433f3d02f3d481f23d443b8415a0f348c 100644
--- a/tidyquestionform.php
+++ b/tidyquestionform.php
@@ -65,7 +65,7 @@ class qtype_stack_tidy_question_form extends moodleform {
             $mform->addElement('header', 'prtnodesheader' . $prtname,
                     stack_string('prtnodesheading', $prtname));
 
-            $graph = $graph = $this->get_prt_graph($prt);
+            $graph = $this->get_prt_graph($prt);
             $newnames = $graph->get_suggested_node_names();
             $mform->addElement('static', $prtname . 'graph', '',
                     stack_abstract_graph_svg_renderer::render($graph, $prtname . 'graphsvg'));
@@ -83,7 +83,7 @@ class qtype_stack_tidy_question_form extends moodleform {
     }
 
     /**
-     * Get a stack_abstract_graph represemtatopm of a PRT.
+     * Get a stack_abstract_graph representation of a PRT.
      * @return stack_abstract_graph.
      */
     protected function get_prt_graph($prt) {