For x, the solution of [x + 2] + [x – 8] > 0 is :

[3, ∞) [4, ∞] [4, ∞) (3, ∞)

[4, ∞)

given [x + 2] + [x – 8] > 0 ⇒ [x] + 2 + [x] – 8 > 0 ⇒ [x] > 3 ⇒ x ∈ [4, ∞) Hence (3) is the correct answer.