If you subtract $\large\frac{1}{2}$ from a number and multiply the result by $\large\frac{1}{2}$ you get $\large\frac{1}{8}$ , What is the number ?

Question

$\begin{array}{1 1} \frac{1}{4} \\ \frac{3}{4}\\ \frac{4}{5} \\ \frac{3}{8} \end{array}$