Let x be the height of the Washington Monument in your drawing. Using the given scale, we can write the proportion:
\(\displaystyle\frac{{x}}{{555}}{f}{t}={1}\frac{\in}{{100}}{f}{t}.\)

\(\displaystyle{x}={1}\in\frac{.}{{100}}{f}{t}{\left({555}{f}{t}\right)}\)

x=5.55in

\(\displaystyle{x}={1}\in\frac{.}{{100}}{f}{t}{\left({555}{f}{t}\right)}\)

x=5.55in