If X = x: x ∈ N Y = 2x: x ∈ N and Z = 5x: x ∈ N then X ∩ Y ∩ Z is equal to

Question

If X = x: x ∈ N Y = 2x: x ∈ N and Z = 5x: x ∈ N then X ∩ Y ∩ Z is equal to (A)  x: x ∈ N  (B)  5x: x ∈ N  (C)  10x: x ∈ N  (D)  2x: x ∈ N

Tardigrade Admin · Accepted Answer

X ∩ Y ∩ Z = L.C.M. of (x, 2x, 5x) = 10x ∀ x ∈ N

Q. If $X = {x : x \in N}$ , $Y = {2 x : x \in N}$ and $Z = {5 x : x \in N}$ then $X \cap Y \cap Z$ is equal to