Which set is an example of the empty set?
Answer and explanation
Correct answer: {x : x is a natural number and x < 1}
An empty set contains no element that satisfies its defining condition. Under the usual school convention that natural numbers start with 1, no natural number is less than 1. Thus option A represents the empty set. Option B contains 1, 2, 3, and 4; option C contains vowels; and option D contains even numbers such as 2, 4, 6, and 8, so those are not empty.
Frequently asked questions
What is the correct answer to this question?
{x : x is a natural number and x < 1}
Why is this the correct answer?
An empty set contains no element that satisfies its defining condition. Under the usual school convention that natural numbers start with 1, no natural number is less than 1. Thus option A represents the empty set. Option B contains 1, 2, 3, and 4; option C contains vowels; and option D contains even numbers such as 2, 4, 6, and 8, so those are not empty.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Common Questions. Topic: General chapter practice.
