Which number is not included in the open interval (2, 5)?
Answer and explanation
Correct answer: 2
An open interval (2, 5) contains every real number strictly greater than 2 and strictly less than 5. The round brackets exclude both endpoints. Thus 3, 4, and 4.9 lie inside the interval, but 2 is not included. Therefore, option A is correct. Notice that 5 would also be excluded, but it is not among the listed choices.
Frequently asked questions
What is the correct answer to this question?
2
Why is this the correct answer?
An open interval (2, 5) contains every real number strictly greater than 2 and strictly less than 5. The round brackets exclude both endpoints. Thus 3, 4, and 4.9 lie inside the interval, but 2 is not included. Therefore, option A is correct. Notice that 5 would also be excluded, but it is not among the listed choices.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Sets and their representations.
