EAN-13 Year IOL 2011 Round Individual Contest Number Problem 5 Writing System EAN-13 Author Hugh Dobbs Average score 4.7 / 20 Download Problem Problems Eesti English (A) English (B) Nederlands Polski Português Slovenščina Svenska Български Русский Српски Download Solution Solutions Eesti English (A) English (B) Nederlands Polski Português Slovenščina Svenska Български Русский Српски