Which of the following is a well-defined set?

Which of the following is a well-defined set?
  1. Collection of all good students in a class
  2. Collection of all natural numbers less than $10$
  3. Collection of beautiful flowers
  4. Collection of tall boys

Solution

A set must be well-defined. Natural numbers $< 10$ is precise. The others use subjective terms.

Asked in: MH-SSC-9

Practice more Sets questions on Aicharya