155 multiple-choice questions on Sets and Functions from Mathematics, each with the correct answer and, where available, a teacher's explanation. Read through them to revise the chapter, then practise the same questions one by one to test yourself.
126. Two circles drawn without overlapping in a Venn diagram show sets that are:
overlapping
equal
subsets of each other
disjoint
Answer: D) disjoint
Explanation: No overlap means no common elements: the sets are disjoint. SLO M-09-A-12 · Understanding
133. In a town survey of 47 people, 20 speak Urdu at home, 19 speak Punjabi at home and 5 speak both. How many people are in exactly one of the two groups?
29
34
13
15
Answer: A) 29
Explanation: At least one = 20 + 19 - 5 = 34; first group only = 15; second group only = 14; exactly one = 29; neither = 47 - 34 = 13. So the answer is 29. SLO M-09-A-14 · Application
Explanation: A function pairs each first element with exactly one second element; the correct one never repeats an x with different y values. SLO M-09-A-16 · Application
142. In a survey of 60 families: 28 read Jang, 25 read Dawn, 20 read Express; 10 read Jang and Dawn, 8 read Dawn and Express, 6 read Jang and Express, and 3 read all three. How many read only Jang?
18
12
15
25
Answer: C) 15
Explanation: Only Jang = 28 - 10 - 6 + 3 = 15 (the triple overlap was subtracted twice, so add it back once). SLO M-09-A-14 · Application
145. In a class of 46 students, 25 play cricket, 26 play hockey and 11 play both. How many students play cricket only?
29
6
14
40
Answer: C) 14
Explanation: At least one = 25 + 26 - 11 = 40; first group only = 14; second group only = 15; exactly one = 29; neither = 46 - 40 = 6. So the answer is 14. SLO M-09-A-14 · Application
148. In a class of 26 students, 11 play cricket, 13 play hockey and 4 play both. How many students are in at least one of the two groups?
7
20
6
16
Answer: B) 20
Explanation: At least one = 11 + 13 - 4 = 20; first group only = 7; second group only = 9; exactly one = 16; neither = 26 - 20 = 6. So the answer is 20. SLO M-09-A-14 · Application