diff --git a/question/type/multichoice/edit_multichoice_form.php b/question/type/multichoice/edit_multichoice_form.php
index e2367e68367..e94c202d97e 100644
--- a/question/type/multichoice/edit_multichoice_form.php
+++ b/question/type/multichoice/edit_multichoice_form.php
@@ -109,9 +109,13 @@ class qtype_multichoice_edit_form extends question_edit_form {
         foreach ($answers as $key => $answer) {
             //check no of choices
             $trimmedanswer = trim($answer['text']);
-            if (empty($trimmedanswer)) {
+            $fraction = (float) $data['fraction'][$key];
+            if (empty($trimmedanswer) && empty($fraction)) {
                 continue;
             }
+            if (empty($trimmedanswer)) {
+                $errors['fraction['.$key.']'] = get_string('errgradesetanswerblank', 'qtype_multichoice');
+            }
 
             $answercount++;
 
diff --git a/question/type/multichoice/lang/en/qtype_multichoice.php b/question/type/multichoice/lang/en/qtype_multichoice.php
index 091b62e9475..ae44717cc7e 100644
--- a/question/type/multichoice/lang/en/qtype_multichoice.php
+++ b/question/type/multichoice/lang/en/qtype_multichoice.php
@@ -41,6 +41,7 @@ $string['clozeaid'] = 'Enter missing word';
 $string['correctansweris'] = 'The correct answer is: {$a}.';
 $string['correctfeedback'] = 'For any correct response';
 $string['editingmultichoice'] = 'Editing a Multiple choice question';
+$string['errgradesetanswerblank'] = 'Grade set, but the Answer is blank';
 $string['errfractionsaddwrong'] = 'The positive grades you have chosen do not add up to 100%<br />Instead, they add up to {$a}%';
 $string['errfractionsnomax'] = 'One of the choices should be 100%, so that it is<br />possible to get a full grade for this question.';
 $string['feedback'] = 'Feedback';