Which of the following sets is not infinite?
Answer and explanation
Correct answer: {x : x ∈ ℕ, x is a factor of 64}
The governing concept is distinguishing finite and infinite sets. The natural-number factors of a fixed number, 64, are limited: {1, 2, 4, 8, 16, 32, 64}; hence option C is finite. In contrast, natural numbers greater than 1000 continue without end, negative integers continue downward without end, and positive multiples 9, 18, 27, ... are infinite. Therefore option C is the only set that is not infinite.
Frequently asked questions
What is the correct answer to this question?
{x : x ∈ ℕ, x is a factor of 64}
Why is this the correct answer?
The governing concept is distinguishing finite and infinite sets. The natural-number factors of a fixed number, 64, are limited: {1, 2, 4, 8, 16, 32, 64}; hence option C is finite. In contrast, natural numbers greater than 1000 continue without end, negative integers continue downward without end, and positive multiples 9, 18, 27, ... are infinite. Therefore option C is the only set that is not infinite.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: The Empty Set, Finite and Infinite Sets, Equal Sets.
