The answer to this question is 300 ft. tall.
Work Step by Step
First you would have to set up a proportion which would be, 1/50=6/x. You would use Cross Product Property to figure out which corresponds with which and you get 1x=300. Because 1x is the same as x, we don't have to further solve it to isolate x leaving us with the answer of a 300 ft. tall building.