We are given proportion as 14/x = 1/2
So first step is to get rid off 2 from denominator,so we multipy both sides by 2
2(14/x) =2(1/2)
28/x =1
Next step is to get rid off x from denominator ,so we multiply both sides of the equation by x
x(28/x) =x(1)
28x/x =x
28 =x
Hence we get value of x =28
So answer is choice d) 28