Hi Gmat_mission.
First, let's find the value of \(x\). We have that \(\frac{4}{5}x=1\) which implies that \(x=\frac{5}{4}\).
Now, we need to compare the numbers \(\frac{4}{5}\) and \(x=\frac{5}{4}\). We do it as follows:
\(\frac{4}{5} ------ 100\% \)
\(\frac{5}{4} ------ y\% \)
Then, $$y=\frac{\frac{5}{4}\cdot100}{\frac{4}{5}}=\frac{125}{\frac{4}{5}}=156.25\%.$$ So, \(x\) is approximately \(56\%\) greater than \(\frac{4}{5}\).
Therefore, the correct answer is the option _B_.
I hope it is clear. <i class="em em---1"></i>