see the attached picture to better understand the problem
step 1
convert in to ft
1 ft is equal-------------> 12 in
x ft------------> 9 in
x=9/12----> x=0.75 ft
200 ft 9 in long------> 200+0.75----> 200.75 ft
we know that
sin 15°=h/200.75-----> h=200.75*sin 15°
where
h is the vertical rise of the escalator
h=51.9579 ft
0.9579 ft convert to in-----> 0.9579*12----> 11.49 in-----> 11 in
h=51 ft 11 in
the answer is
51 ft 11 in