How many elements are in A = {x : x ∈ N, x is divisible by 5 and x < 40}?
Advertisement
Answer and explanation
Correct answer: 7
The natural numbers less than 40 that are divisible by 5 are 5, 10, 15, 20, 25, 30, and 35. The number 40 is excluded because the condition is x < 40, not x ≤ 40. There are seven listed elements, so the set is finite and its cardinality is 7. Therefore, option A is correct.
Frequently asked questions
What is the correct answer to this question?
7
Why is this the correct answer?
The natural numbers less than 40 that are divisible by 5 are 5, 10, 15, 20, 25, 30, and 35. The number 40 is excluded because the condition is x < 40, not x ≤ 40. There are seven listed elements, so the set is finite and its cardinality is 7. Therefore, option A is correct.
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.
Advertisement