Mathematics for IGCSE & O level - Sets (Section 3)
1
How many students study at least one subject in this scenario: 25 students study history, 20 study geography, and 10 study both?
Răspuns
(B)
45
2
If n(A) = 5 and n(B) = 7, what is the maximum possible value of n(A ∪ B)?
Răspuns
(C)
12
3
Consider the sets: A = {1, 2, 3, 4}, B = {3, 4, 5, 6}. Which of the following is/are TRUE?
Răspuns
A
B
D
4
What does the shaded region represent in a Venn diagram that consists of two overlapping circles if the shaded region includes only the area of the intersection?
Răspuns
(C)
A ∩ B
5
Which of the following is not a way to define a set?
Răspuns
(D)
Giving an example of an element in the set.
6
If the universal set is positive integers less than 5, and A = {prime numbers}, what are the elements of A?
Răspuns
(B)
{2, 3}
7
If n(A) = 7, n(B) = 9 and n(A ∩ B) = 4, what is n(A ∪ B)?
Răspuns
(B)
16
8
Which of these is an example of a set defined by a rule?
Răspuns
(C)
{x | x is an even number}
9
What is the result of A ∩ Ø, where Ø is the empty set?
Răspuns
(B)
Ø
10
If A = {red, green, blue} and B = {blue, yellow, orange}, what is the result of A - B?
Răspuns
(A)
{red, green}
11
Which of the following would contain all the elements in set P and all the elements in set Q?
Răspuns
(B)
P ∪ Q
12
What is the meaning of the symbol ∩?
Răspuns
(C)
Intersection of sets
13
If A = {x | x is a letter in the word 'apple'} and B = {x | x is a letter in the word 'banana'}, then A ∩ B = ?
Răspuns
(A)
{a, p}
14
In a Venn diagram, how many sections are created by the intersection of three sets?
Răspuns
(D)
8
15
What is the meaning of the symbol ∪?
Răspuns
(B)
Union of sets
16
Venn diagrams are a way of showing ________ between sets.
Răspuns
(C)
Relationships
17
If A = {1, 2, 3} and B = {3, 1, 2}, what is the relationship between A and B?
Răspuns
(C)
A = B
18
If A = {1, 2, 3} and B = {3, 4, 5}, then A ∪ B is equal to:
Răspuns
(B)
{1, 2, 3, 4, 5}
19
If set A = {1, 2, 3} and set B = {4, 5, 6}, which statement is true?
Răspuns
(B)
A ∩ B = {}
20
What is the term for a set that contains an infinite number of elements?
Răspuns
(B)
Infinite set
21
In the context of set theory, what does the notation '∉' mean?
Răspuns
(B)
Is not an element of
22
If A = {1, 2, 3} and B = {3, 4, 5}, then A ∩ B is equal to:
Răspuns
(A)
{3}
23
If A and B are disjoint sets, what is A ∩ B?
Răspuns
(C)
{}
24
In a survey, 60 people like coffee, 50 like tea, and 30 like both. How many people like coffee or tea?
Răspuns
(A)
80
25
If A = {1, 2, 3, 4, 5} and B = {5, 6, 7}, what is A ∪ B?
Răspuns
(B)
{1, 2, 3, 4, 5, 6, 7}
26
Which set operation is represented by the shaded region in a Venn diagram where the shaded area includes only the area of set P?
Răspuns
(C)
P
27
If A = {1, 2, 3} and the universal set U = {1, 2, 3, 4, 5}, then A' is:
Răspuns
(B)
{4, 5}
28
How many subsets does a set with three elements have?
Răspuns
(C)
8
29
Which of the following would represent the shaded area if the shaded area in the Venn diagram includes everything in set P but exclude everything in set Q?
Răspuns
(C)
P \ Q
30
What does the shaded area in a Venn diagram represent if P and Q are two sets and the shaded area covers everything outside of both sets?
Răspuns
(C)
(P ∪ Q)'
31
What does it mean when a set is described as a 'finite set'?
Răspuns
(C)
The set has a definite, limited number of elements.
32
What is the result of the following set operation: A ∪ (A ∩ B)?
Răspuns
(A)
A
33
In a Venn diagram, the universal set is shown by a ________.
Răspuns
(B)
Rectangle
34
If A is a subset of B (A ⊆ B), what does this mean?
Răspuns
(A)
All elements of A are also in B
35
Given: U = {a, b, c, d, e}, A = {a, b}, B = {c, d}. What is A' ∩ B?
Răspuns
(B)
{c, d}
36
In a class of 40 students, 20 study physics, 18 study chemistry, and 8 study both. How many students study neither physics nor chemistry?
Răspuns
(B)
12
37
A set is a collection of ________.
Răspuns
(A)
Numbers, shapes, letters, points or other objects
38
If A ⊆ B, which of the following is ALWAYS true?
Răspuns
(D)
A ∪ B = B
39
Which of the following are correct regarding how to define a set?
Răspuns
A
B
40
If P and Q are disjoint sets, then:
Răspuns
(C)
P ∩ Q = Ø
41
Which of the following describes the number of subsets a set can have?
Răspuns
(B)
2^n
42
In a class of 50 students, 30 play football, 25 play basketball, and 10 play both. How many students play only football?
Răspuns
(C)
20
43
Which of the following statements is/are true about subsets?
Răspuns
A
B
C
44
Which statement is true about the intersection of a set and its complement?
Răspuns
(C)
It is the empty set.
45
Which of the following correctly describes the relationship between the sets represented in a Venn diagram where one circle is fully contained within another circle?
Răspuns
(B)
One set is a subset of the other.
46
If a set has 10 elements, how many of its subsets will have 2 elements?
Răspuns
(B)
45
47
Which of the following is not a property of set operations?
Răspuns
(D)
Non-commutativity of intersection
48
In a survey of 50 students, 20 like apples, 25 like bananas, and 10 like both. How many students like either apples or bananas?
Răspuns
(B)
40
49
Which of the following represents the De Morgan's Law?
Răspuns
(C)
(A ∪ B)' = A' ∩ B'
50
If n(U) = 20, n(A) = 8, and n(B) = 10, and n(A ∩ B) = 3, what is n((A ∪ B)')?
