If A = {1, 2, 3}, B = {3, 4}, and C = {4, 5}, what is A ∪ B ∪ C?
Answer and explanation
Correct answer: {1, 2, 3, 4, 5}
A union contains every distinct element that occurs in at least one of the given sets. Begin with A = {1, 2, 3}, add the new element 4 from B, and then add the new element 5 from C. The elements 3 and 4 are repeated in different sets, but a set does not list duplicates. Thus A ∪ B ∪ C = {1, 2, 3, 4, 5}.
Frequently asked questions
What is the correct answer to this question?
{1, 2, 3, 4, 5}
Why is this the correct answer?
A union contains every distinct element that occurs in at least one of the given sets. Begin with A = {1, 2, 3}, add the new element 4 from B, and then add the new element 5 from C. The elements 3 and 4 are repeated in different sets, but a set does not list duplicates. Thus A ∪ B ∪ C = {1, 2, 3, 4, 5}.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Operations on Sets (Union, Intersection, Difference).
