Exam-style question
Try this first
Which statement about the natural number 17 is correct?.
- A.17 is not in ℕ because it is greater than zero.
- B.17 is in ℕ because it is one of 0, 1, 2, 3, ….
- C.17 is not in ℕ because natural numbers must be less than 10.
- D.17 is in ℕ only when it is written as a decimal.
Model answer
What a good answer should say
- 17 is in ℕ because it is one of 0, 1, 2, 3, ….
Explanation
Why this works
The ellipsis in ℕ = {0, 1, 2, 3, …} indicates that the sequence continues, so 17 is included.
Common mistake
No common mistake is linked to this question yet.