AMO 2027 Grades 9-11 SET 5 - Self-study Question 8

Mel sells jumbo cheesy pretzel nuggets in packs of 5 (“diet”), 6 (“share”), and 11 (“party”). What is the greatest total number of nuggets that cannot be bought exactly? For example, 15 can be bought but 7 cannot. Any nonnegative whole number of each pack may be bought.

Enter one positive integer, without units.