Practice Venn Diagram questions covering relationships between classes such as doctors, teachers, and parents, syllogism-style set logic, and identifying the correct diagram for a given group of items.
Question 1
Study the diagram below and answer the question.

How many swimmers are neither cyclists nor runners?

How many swimmers are neither cyclists nor runners?
Explanation
The number in the part of the Swimmers circle that lies outside the other two circles is 21.
Question 2
Study the diagram below and answer the question.

How many cyclists are neither swimmers nor runners?

How many cyclists are neither swimmers nor runners?
Explanation
The number in the part of the Cyclists circle that lies outside the other two circles is 13.
Question 3
Study the diagram below and answer the question.

How many swimmers are cyclists?

How many swimmers are cyclists?
Explanation
Swimmers who are cyclists are in the overlap of those two circles, which has two parts: 5 (not runners) and 2 (also runners). Total = 5 + 2 = 7.
Question 4
Study the diagram below and answer the question.

How many runners are both cyclists and swimmers?

How many runners are both cyclists and swimmers?
Explanation
Those who belong to all three groups are in the centre, where all three circles overlap. That number is 2.
Question 5
Study the diagram below and answer the question.

How many runners are neither swimmers nor cyclists?

How many runners are neither swimmers nor cyclists?
Explanation
The number in the part of the Runners circle that lies outside the other two circles is 17.
Question 6
Study the diagram below and answer the question.

How many singers are neither dancers nor actors?

How many singers are neither dancers nor actors?
Explanation
The number in the part of the Singers circle that lies outside the other two circles is 14.
Question 7
Study the diagram below and answer the question.

How many dancers are neither singers nor actors?

How many dancers are neither singers nor actors?
Explanation
The number in the part of the Dancers circle that lies outside the other two circles is 19.
Question 8
Study the diagram below and answer the question.

How many singers are dancers?

How many singers are dancers?
Explanation
Singers who are dancers are in the overlap of those two circles, which has two parts: 6 (not actors) and 4 (also actors). Total = 6 + 4 = 10.
Question 9
Study the diagram below and answer the question.

How many actors are both dancers and singers?

How many actors are both dancers and singers?
Explanation
Those who belong to all three groups are in the centre, where all three circles overlap. That number is 4.
Question 10
Study the diagram below and answer the question.

How many actors are neither singers nor dancers?

How many actors are neither singers nor dancers?
Explanation
The number in the part of the Actors circle that lies outside the other two circles is 11.
Question 11
Which of the following diagrams indicates the best relation between Pilot, Carpenter and Teacher?
Explanation
All three are different professions, so no circle overlaps another. Three separate circles are shown in diagram C.
Question 12
Which of the following diagrams indicates the best relation between Hospital, Medicines and Doctors?
Explanation
Medicines and Doctors are different from each other, but both are found in a Hospital. So two separate circles lie inside one larger circle, as in diagram D.
Question 13
Which of the following diagrams indicates the best relation between Men, Fathers and Doctors?
Explanation
All fathers are men, so the Fathers circle lies inside the Men circle. Some fathers and some men may be doctors, so the Doctors circle overlaps both the Fathers circle and the Men circle (and also extends outside Men, since not all doctors are men). This is diagram B.
Question 14
Which of the following diagrams indicates the best relation between Income, Salary and Interest?
Explanation
Salary and Interest are different from each other, but both of them are parts of Income. So two separate circles lie inside one larger circle, as in diagram A.
Question 15
Which of the following diagrams indicates the best relation between Passengers, Aeroplane and Ship?
Explanation
Aeroplane and Ship are different from each other (their circles do not overlap), but some passengers travel by aeroplane and some travel by ship, so the Passengers circle overlaps both. This is the chain of three overlapping circles in diagram C.
Question 16
Out of a total of 150 students, 45 passed in Accounts, 45 in Economics and 50 in Maths, 30 in both Accounts and Maths, 32 in both Maths and Economics, 35 in both Accounts and Economics, and 25 students passed in all three subjects. Find the number who passed in at least one of the subjects.
Explanation
Using the inclusion-exclusion principle: Passed at least one = 45 + 45 + 50 - 30 - 32 - 35 + 25 = 68
Question 17
A town has a total population of 50,000. Out of it, 28,000 read the newspaper X and 23,000 read Y while 4,000 read both the papers. The number of persons not reading X and Y both is
Explanation
Reading at least one paper = 28,000 + 23,000 - 4,000 = 47,000
Not reading either paper = 50,000 - 47,000 = 3,000
Not reading either paper = 50,000 - 47,000 = 3,000
Question 18
Out of 1000 persons, 25 per cent were industrial workers and the rest were agricultural workers. 300 persons enjoyed World Cup matches on TV. 30 per cent of the people who had not watched World Cup matches were industrial workers. What is the number of agricultural workers who had enjoyed World Cup matches on TV?
Explanation
Industrial workers = 250, Agricultural workers = 750.
Non-watchers = 1000 - 300 = 700. Industrial among non-watchers = 30% of 700 = 210.
So industrial watchers = 250 - 210 = 40.
Agricultural watchers = Total watchers - Industrial watchers = 300 - 40 = 260
Non-watchers = 1000 - 300 = 700. Industrial among non-watchers = 30% of 700 = 210.
So industrial watchers = 250 - 210 = 40.
Agricultural watchers = Total watchers - Industrial watchers = 300 - 40 = 260
Question 19
There are 40 students; 30 of them passed in English, 25 of them passed in Maths and 15 of them passed in both. Assuming that every student passed at least in one subject, how many students passed in English only but not in Maths?
Explanation
English only = Total English - Both = 30 - 15 = 15
Question 20
In a survey of 300 companies, the number of companies using different media -- Newspapers (N), Radio (R) and Television (T) -- are as follows:
n(N) = 200, n(R) = 100, n(T) = 40, n(N∩R) = 50, n(R∩T) = 20, n(N∩T) = 25, and n(N∩R∩T) = 5.
Find the number of companies using none of these media.
n(N) = 200, n(R) = 100, n(T) = 40, n(N∩R) = 50, n(R∩T) = 20, n(N∩T) = 25, and n(N∩R∩T) = 5.
Find the number of companies using none of these media.
Explanation
|N∪R∪T| = |N| + |R| + |T| - |N∩R| - |R∩T| - |N∩T| + |N∩R∩T|
= 200 + 100 + 40 - 50 - 20 - 25 + 5 = 340 - 95 + 5 = 250
Companies using none = 300 - 250 = 50
= 200 + 100 + 40 - 50 - 20 - 25 + 5 = 340 - 95 + 5 = 250
Companies using none = 300 - 250 = 50
Question 21
In a town of 20,000 families, it was found that 40% families buy newspaper A, 20% families buy newspaper B and 10% families buy newspaper C, 5% families buy A and B, 3% buy B and C and 4% buy A and C. If 2% families buy all the three newspapers, then the number of families which buy A only is:
Explanation
|A| = 8000, |A∩B| = 1000, |A∩C| = 800, |A∩B∩C| = 400 (all out of 20,000 families)
A only = |A| - |A∩B| - |A∩C| + |A∩B∩C|
= 8000 - 1000 - 800 + 400 = 6600
A only = |A| - |A∩B| - |A∩C| + |A∩B∩C|
= 8000 - 1000 - 800 + 400 = 6600
Question 22
Out of total 150 students, 45 passed in Accounts, 45 in Economics and 50 in Maths, 30 in both Accounts and Maths, 32 in both Maths and Economics, 35 in both Accounts and Economics, 25 students passed in all the three subjects. Find the number who passed at least in any one of the subjects:
Explanation
By the inclusion-exclusion principle: |A ∪ E ∪ M| = |A| + |E| + |M| - |A ∩ M| - |M ∩ E| - |A ∩ E| + |A ∩ E ∩ M| = 45 + 45 + 50 - 30 - 32 - 35 + 25 = 140 - 97 + 25 = 68