Operations on Sets · Form 4
Operations on Sets: Practice Questions
Original SPM-style practice questions for Operations on Sets, each with full worked solutions, Paper 1 multiple-choice and Paper 2 structured.
Original practice questions for Operations on Sets, in the style of Mathematics Paper 1 (Objective) and Mathematics Paper 2 (Subjective). Each answer is worked so you can check your method, not just the result.
Multiple-choice (Paper 1 style)
Question 1
Given A = {2, 3, 5, 7, 11} and B = {1, 3, 5, 7, 9}, find A ∩ B.
- A. {3, 5}
- B. {1, 2, 9, 11}
- C. {3, 5, 7}
- D. {1, 2, 3, 5, 7, 9, 11}
Question 2
Given P = {k, l, m} and Q = {l, m, n, o}, find P ∪ Q.
- A. {l, m}
- B. {k, l, m, n, o}
- C. {k, n, o}
- D. {k, l, m}
Question 3
The universal set is ξ = {x : 1 ≤ x ≤ 10, x is an integer}. If A = {2, 4, 6, 8, 10}, find A'.
- A. {2, 4, 6, 8, 10}
- B. {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
- C. { }
- D. {1, 3, 5, 7, 9}
Question 4
Given n(A) = 18, n(B) = 12 and n(A ∩ B) = 5, find n(A ∪ B).
- A. 30
- B. 20
- C. 25
- D. 35
Question 5
In a Venn diagram, the shaded region contains all elements that are in set A but not in set B. Which notation represents the shaded region?
- A. A ∩ B'
- B. A' ∩ B
- C. A ∩ B
- D. (A ∪ B)'
Question 6
Given ξ = {1, 2, 3, 4, 5, 6, 7, 8}, A = {1, 2, 3, 4} and B = {3, 4, 5, 6}, find (A ∩ B)'.
- A. {3, 4}
- B. {1, 2, 5, 6, 7, 8}
- C. {7, 8}
- D. {1, 2, 5, 6}
Question 7
The shaded region of a Venn diagram represents (A ∪ B)'. By De Morgan's law, this is equal to which set?
- A. A' ∪ B'
- B. A ∩ B
- C. A' ∩ B'
- D. A ∪ B
Question 8
Given n(ξ) = 30 and n(A ∪ B) = 24, find n((A ∪ B)').
- A. 24
- B. 54
- C. 4
- D. 6
Question 9
If A ⊂ B, which of the following is equal to A ∩ B?
- A. A
- B. B
- C. ∅
- D. A ∪ B
Question 10
In a group of 50 students, 30 like tea and 25 like coffee, while 10 like both. How many students like neither drink?
- A. 45
- B. 5
- C. 10
- D. 15
Structured (Paper 2 style)
Question 1 (6 marks)
In a group of 60 students, 35 joined the Science Club (S), 28 joined the Mathematics Club (M) and 12 joined both clubs. (a) Find n(S ∪ M).
(b) Find the number of students who joined only one club. (c) Find the number of students who joined neither club.
- n(S ∪ M) = n(S) + n(M) − n(S ∩ M) = 35 + 28 − 12 = 51 students.
- Science only = 35 − 12 = 23; Mathematics only = 28 − 12 = 16.
- Students in only one club = 23 + 16 = 39 students.
- Students in neither club = n(ξ) − n(S ∪ M) = 60 − 51 = 9 students.
Question 2 (7 marks)
The universal set is ξ = {x : 1 ≤ x ≤ 15, x is an integer}. Set A is the set of multiples of 3 and set B is the set of factors of 12.
(a) List all elements of A and of B. (b) Find A ∩ B.
(c) Find A ∪ B. (d) Find (A ∪ B)'.
- Multiples of 3 up to 15: A = {3, 6, 9, 12, 15}.
- Factors of 12 within 1 to 15: B = {1, 2, 3, 4, 6, 12}.
- A ∩ B = common elements = {3, 6, 12}.
- A ∪ B = all elements listed once = {1, 2, 3, 4, 6, 9, 12, 15}.
- (A ∪ B)' = elements of ξ not in A ∪ B = {5, 7, 8, 10, 11, 13, 14}.
Question 3 (6 marks)
In a class of 40 students, 24 study Physics (P), 25 study Chemistry (C) and 6 study neither subject. Let x be the number who study both subjects.
(a) Form an equation in x and solve it to find n(P ∩ C). (b) Find the number who study Physics only.
(c) Find the number who study Chemistry only.
- Students studying at least one subject = 40 − 6 = 34, so n(P ∪ C) = 34.
- Using n(P ∪ C) = n(P) + n(C) − x: 34 = 24 + 25 − x.
- 34 = 49 − x, so x = 49 − 34 = 15; thus n(P ∩ C) = 15.
- Physics only = n(P) − x = 24 − 15 = 9.
- Chemistry only = n(C) − x = 25 − 15 = 10.
Question 4 (6 marks)
The universal set is ξ = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, with A = {2, 3, 5, 7} and B = {1, 2, 3, 4, 5}. (a) List A' and B'.
(b) Find (A ∩ B)'. (c) Find A' ∪ B' and hence verify that (A ∩ B)' = A' ∪ B'.
- A' = elements of ξ not in A = {1, 4, 6, 8, 9, 10}.
- B' = elements of ξ not in B = {6, 7, 8, 9, 10}.
- A ∩ B = {2, 3, 5}, so (A ∩ B)' = {1, 4, 6, 7, 8, 9, 10}.
- A' ∪ B' = {1, 4, 6, 8, 9, 10} ∪ {6, 7, 8, 9, 10} = {1, 4, 6, 7, 8, 9, 10}.
- Both results equal {1, 4, 6, 7, 8, 9, 10}, verifying De Morgan's law (A ∩ B)' = A' ∪ B'.
Source:SPM: Format Pentaksiran mulai 2021, Matematik (1449)
Frequently asked questions
What's the difference between the Paper 1 and Paper 2 questions in this sets practice set?
Paper 1 questions are multiple-choice, checking quick recognition of union, intersection, and complement notation. Paper 2 questions ask you to draw and shade Venn diagrams, list set elements, and explain your reasoning in full steps, practising the working that Paper 2 marks reward.
Why attempt each set question myself before checking the worked solution?
Shading a Venn diagram correctly takes practice reading which regions a question actually describes. Attempting it yourself first shows whether you can translate set notation into a diagram under exam time pressure, rather than just recognising a correct diagram once it's drawn for you.
What common mistakes appear in operations on sets questions?
Students often shade the wrong region for a complement, confuse ∩ with ∪, or forget elements shared between two sets when listing them once. Working through this practice set helps you catch these slips before they cost marks in the real exam.