10 questions · Form 4 Mathematics Bab 3: Operations on Sets
10 questions · plays in fullscreen
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. Given ξ = {1, 2, 3, 4, 5}, A = {1, 2}, B = {3, 4}. Find A' ∩ B'.
Answer: A
A' = {3, 4, 5} and B' = {1, 2, 5}. The intersection A' ∩ B' = {5}. (By De Morgan's Law, A' ∩ B' = (A ∪ B)' = {5}).
2. Given the universal set ξ = {1, 2, 3, 4, 5, 6, 7, 8} and set P = {2, 4, 6, 8}. Find P'.
Answer: B
The complement P' consists of all elements in the universal set ξ that are NOT in set P. Thus P' = {1, 3, 5, 7}.
3. Given universal set ξ = {x : x is an integer, 1 ≤ x ≤ 10}, set A = {2, 4, 6, 8, 10}, and set B = {3, 6, 9}. Find (A ∩ B)'.
Answer: B
A ∩ B = {6}. Therefore, (A ∩ B)' includes all elements in ξ except 6, which is {1, 2, 3, 4, 5, 7, 8, 9, 10}.
4. Given set K = {factors of 12} and set L = {factors of 18}. Find n(K ∩ L).
Answer: C
K = {1, 2, 3, 4, 6, 12} and L = {1, 2, 3, 6, 9, 18}. The intersection K ∩ L = {1, 2, 3, 6}. Therefore, n(K ∩ L) = 4.
5. Given A ⊂ B (A is a subset of B). What is A ∩ B?
Answer: A
If set A is entirely contained within set B (A ⊂ B), all elements of A are in B. Thus, the intersection of A and B is set A itself.
6. Given ξ = {1, 2, 3, 4, 5, 6, 7}, P = {1, 3, 5}, Q = {2, 3, 4}. Find (P ∪ Q)'.
Answer: C
P ∪ Q = {1, 2, 3, 4, 5}. The complement (P ∪ Q)' consists of remaining elements in ξ, which are {6, 7}.
7. Given set M = {a, b, c} and set N = {c, d, e}. What is A ∪ B?
Answer: C
The union M ∪ N contains all unique elements present in set M, set N, or both, which gives {a, b, c, d, e}.
8. Given set A = {x : x is a letter in 'KSSM'}. Find n(A).
Answer: B
Sets do not contain duplicate elements. Set A = {'K', 'S', 'M'}, so n(A) = 3.
9. In a survey of 30 pupils, 18 like Mathematics (M) and 15 like Science (S). If 5 like neither, how many like BOTH Mathematics and Science?
Answer: A
n(M ∪ S) = 30 - 5 = 25 pupils. n(M ∩ S) = n(M) + n(S) - n(M ∪ S) = 18 + 15 - 25 = 8 pupils.
10. Given sets P = {red, blue}, Q = {yellow, blue}, and R = {green, red}. Find P ∩ Q ∩ R.
Answer: D
There is no single color present in all three sets simultaneously. Thus, P ∩ Q ∩ R is the empty set (∅).