diff --git a/mod/quiz/renderer.php b/mod/quiz/renderer.php
index 7ea2812ed55..65622b1c72c 100644
--- a/mod/quiz/renderer.php
+++ b/mod/quiz/renderer.php
@@ -1307,10 +1307,12 @@ class mod_quiz_renderer extends plugin_renderer_base {
      *
      * @param \core\chart_base $chart The chart.
      * @param string $title The title to display above the graph.
+     * @param array $attrs extra container html attributes.
      * @return string HTML fragment for the graph.
      */
-    public function chart(\core\chart_base $chart, $title) {
-        return $this->heading($title, 3) . html_writer::tag('div', $this->render($chart), array('class' => 'graph'));
+    public function chart(\core\chart_base $chart, $title, $attrs = []) {
+        return $this->heading($title, 3) . html_writer::tag('div',
+            $this->render($chart), array_merge(['class' => 'graph'], $attrs));
     }
 
     /**
diff --git a/mod/quiz/report/overview/report.php b/mod/quiz/report/overview/report.php
index 05271e4806d..9c4cf8e98a3 100644
--- a/mod/quiz/report/overview/report.php
+++ b/mod/quiz/report/overview/report.php
@@ -225,7 +225,8 @@ class quiz_overview_report extends quiz_attempts_report {
                     $data = quiz_report_grade_bands($bandwidth, $bands, $quiz->id, $groupstudentsjoins);
                     $chart = self::get_chart($labels, $data);
                     $graphname = get_string('overviewreportgraphgroup', 'quiz_overview', groups_get_group_name($currentgroup));
-                    echo $output->chart($chart, $graphname);
+                    // Numerical range data should display in LTR even for RTL languages.
+                    echo $output->chart($chart, $graphname, ['dir' => 'ltr']);
                 }
             }
 
@@ -233,7 +234,8 @@ class quiz_overview_report extends quiz_attempts_report {
                 $data = quiz_report_grade_bands($bandwidth, $bands, $quiz->id, new \core\dml\sql_join());
                 $chart = self::get_chart($labels, $data);
                 $graphname = get_string('overviewreportgraph', 'quiz_overview');
-                echo $output->chart($chart, $graphname);
+                // Numerical range data should display in LTR even for RTL languages.
+                echo $output->chart($chart, $graphname, ['dir' => 'ltr']);
             }
         }
         return true;