Free practice on Types of Sets for Class 6, following the Cameroon primary school curriculum (English subsystem). Every answer is explained, so a parent who is not sure of the answer can still help.
Universal: everything in the discussion. Subset: a smaller set inside a bigger one. Finite: countable. Infinite: never-ending. Equal: same members. Equivalent: same size, different members. Disjoint: no shared members.
| Type | Example |
|---|---|
| Universal | {all pupils} |
| Subset | {Class 6 pupils} ⊂ {all pupils} |
| Finite | {days of week} |
| Infinite | {1, 2, 3, …} |
| Equal | {1,2,3} = {1,2,3} |
| Equivalent | {a,b,c} ↔ {1,2,3} |
| Disjoint | {cats} ∩ {dogs} = ∅ |
Union (A ∪ B): all members of A and B, no repeats. Intersection (A ∩ B): only members in BOTH. Difference (A − B): in A but not in B. Complement (A′): in the universal set but NOT in A.
| Operation | Meaning |
|---|---|
| A ∪ B | everything in A or B |
| A ∩ B | only what is in both |
| A − B | in A but not in B |
| A′ | in universal set but not in A |
| n(A) | number of members of A |
Draw two overlapping circles for A and B. Place shared members in the overlap; members only in A go to A's outside. Handy for word problems like 'How many pupils do BOTH football and music?'
A = {2, 4, 6} and B = {4, 6, 8}. What is A ∩ B?
Answer: B. {4, 6}
The intersection holds the members found in BOTH sets.
A = {2, 4, 6} and B = {4, 6, 8}. What is A ∪ B?
Answer: C. {2, 4, 6, 8}
The union puts all members together, each written once.
How many members are in the set {mango, pawpaw, guava, orange, plum}?
Write your answer, then check below.
Answer: 5
The set of pupils in your class who are 40 metres tall is:
Answer: C. the empty set
Nobody is 40 metres tall — the set has no members.
{days of the week} and {colours of the rainbow} both have 7 members. They are:
Answer: B. equivalent sets
Same NUMBER of members = equivalent; same members = equal.
The app holds every question on this page and hundreds more, works with no internet after the first load, and costs nothing. It fits on a shared phone.
