If C₂ = {x ∈ ℕ : x is divisible by both 2 and 3 and x ≤ 18}, then what is C₂?
Answer and explanation
Correct answer: {6, 12, 18}
A natural number divisible by both 2 and 3 must be divisible by their least common multiple, lcm(2, 3) = 6. The positive multiples of 6 not exceeding 18 are 6, 12, and 18. Therefore C₂ = {6, 12, 18}. Numbers divisible by only one of 2 or 3 do not satisfy the word both.
Frequently asked questions
What is the correct answer to this question?
{6, 12, 18}
Why is this the correct answer?
A natural number divisible by both 2 and 3 must be divisible by their least common multiple, lcm(2, 3) = 6. The positive multiples of 6 not exceeding 18 are 6, 12, and 18. Therefore C₂ = {6, 12, 18}. Numbers divisible by only one of 2 or 3 do not satisfy the word both.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Sets and their representations.