[Retric]

Adding "average" helps it parse the question.

height Empire State Building divided by average height human

= 235

height Empire State Building divided by height human

Fails

[evilneanderthal]

Neat.

a billion light years / average height human * (1/9) furlong / age universe = 1.01 c (speed of light)

Very neat.

[las3rjock]

I was pretty sure I tried every permutation of the words "average," "height," and "human," but I guess I didn't. Bravo.