If A = {a, a, b, b, c} and B = {a, b, c}, what is the correct relation?
Answer and explanation
Correct answer: A = B
In ordinary set notation, an element is recorded only once; repeated listings do not create new elements. Therefore A = {a, b, c} after removing the repeated a and b. This is exactly the set B, so A = B. Option B incorrectly treats a set like an ordered list or multiset. Option C is false because B is not a proper subset of A when the two sets are equal. Option D is false because their intersection is {a, b, c}, not the empty set.
Frequently asked questions
What is the correct answer to this question?
A = B
Why is this the correct answer?
In ordinary set notation, an element is recorded only once; repeated listings do not create new elements. Therefore A = {a, b, c} after removing the repeated a and b. This is exactly the set B, so A = B. Option B incorrectly treats a set like an ordered list or multiset. Option C is false because B is not a proper subset of A when the two sets are equal. Option D is false because their intersection is {a, b, c}, not the empty set.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Equal sets and Subsets.
