Venn Diagrams

Task goals

• Read a region's value directly off a two- or three-set Venn diagram, and identify what a shaded region represents in words.
• Calculate n(A), n(A union B), n(A intersect B), and n(A') (the complement) from a Venn diagram's regions.
• Work backwards from a stated total and known regions to find one missing region.
• Apply the inclusion-exclusion formula n(A union B) = n(A) + n(B) - n(A intersect B).
• Read cardinalities from a three-set Venn diagram, including regions belonging to two or three sets at once.
• Combine a Venn diagram with basic algebra to find an unknown region given the total, and identify the common error of adding the wrong two regions together.