If \(A=\{x\in\mathbb{N}:x\le 40,\ 4\mid x\}\) and \(B=\{x\in\mathbb{N}:x\le 40,\ 6\mid x\}\), what is \(A\cap B\)?
Answer and explanation
Correct answer: \(\{12,24,36\}\)
An element in \(A\cap B\) must be divisible by both 4 and 6. Such numbers are multiples of their least common multiple, \(\operatorname{lcm}(4,6)=12\). The positive multiples of 12 not exceeding 40 are 12, 24, and 36. Therefore, \(A\cap B=\{12,24,36\}\), making option A correct.
Frequently asked questions
What is the correct answer to this question?
\(\{12,24,36\}\)
Why is this the correct answer?
An element in \(A\cap B\) must be divisible by both 4 and 6. Such numbers are multiples of their least common multiple, \(\operatorname{lcm}(4,6)=12\). The positive multiples of 12 not exceeding 40 are 12, 24, and 36. Therefore, \(A\cap B=\{12,24,36\}\), making option A correct.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Operations on Sets (Union, Intersection, Difference).