Answer:
407.22 foot is the boat from the base of the lighthouse
Step-by-step explanation:
Given the statement: An observer on top of a 50-foot tall lighthouse sees a boat at a 7° angle of depression.
Let x foot be the distance of the object(boat) from the base of the lighthouse
Angle of depression = 
[Alternate angle]
In triangle CAB:
To find AB = x foot.
Using tangent ratio:


Here, BC = 50 foot and 
then;

or


Simplify:
AB = x = 407.217321 foot
Therefore, the boat from the base of the light house is, 407.22'
There's a bunch of them like if you simplify you could get 3/4.I'll give you some more.
Examples:14/16 21/24 28/32 and 35/40.
My brain was getting tired to think...but there's more.
Hope this helps :D
321-207 is actually equals to 114 but I mean the equation is false