Logical Venn Diagram Level 2 Practice Quiz: Set Counting and Class Relations
This is the Level 2 set of logical Venn diagram practice questions on Aptitude360. It mixes numerical two-set and three-set counting problems with diagram-matching questions on how classes relate. Every question comes with a worked solution explaining the region-by-region method.
Topics covered in this Venn diagram Level 2 set
- Two-set problems that find how many like both, only one or neither of two things
- Three-set problems on sports, subjects, languages and skills using all seven regions
- Percentage-based surveys converted to actual numbers of people
- Minimum and maximum possible overlap of two or three groups
- Counting cases described as exactly one, at most one and only one
- Choosing the diagram for classes such as Kerala, India and Asia or Pens, Pencils and Stationery
- Number-based classes such as even numbers, prime numbers and multiples
Key set formulas for Venn diagram questions
- Union of two sets: \( n(A\cup B)=n(A)+n(B)-n(A\cap B) \)
- Neither of the two: \( n(U)-n(A\cup B) \)
- Exactly one of two: \( n(A)+n(B)-2\,n(A\cap B) \)
- Union of three sets: \( n(A\cup B\cup C)=\sum n(A)-\sum n(A\cap B)+n(A\cap B\cap C) \)
- Least overlap of two: \( n(A\cap B)\ge n(A)+n(B)-n(U) \)
- Greatest overlap of two: \( n(A\cap B)\le \min\{n(A),n(B)\} \)
Revision tips for logical Venn diagram problems
- Fill a three-set diagram from the centre outwards: the common region first, then the pairs, then the only regions.
- Subtract the neither group from the total before applying the union formula.
- In class-relation questions, ask whether one class lies wholly inside another, overlaps it or shares nothing with it.
- Watch the wording carefully: both includes those who like all three, while exactly two does not.
Who should practise this Level 2 Venn set
Students who already know basic Venn diagrams and want medium-level practice for aptitude and reasoning sections of competitive exams.