Given 12x < 50

i. x ∈ R

When x is a real number, the solution of the given inequation is.

ii. x ∈ Z

As, when x is an integer, the maximum possible value of x is 4.

Thus, the solution of the given inequation is {…, –2, –1, 0, 1, 2, 3, 4}.

iii. x ∈ N

As, when x is a natural number, the maximum possible value of x is 4 and we know the natural numbers start from 1.

Thus, the solution of the given inequation is {1, 2, 3, 4}.