Chapter 2 - Set Theory - 2.4 Set Operations and Venn Diagrams with Three Sets - Exercise Set 2.4 - Page 92: 44

(A∪B∪C)'= {13}

(A∪B∪C)' The set (A∪B∪C)', represents the regions that does not belongs to A, B, C. From the given Venn diagram we can conclude that the region VIII belongs to set (A∪B∪C)'. The element of these region is 13. So, (A∪B∪C)'= {13}