Calculate the length of a 120m (as measured by the astronaut) spaceship travelling at 0.85c as measured by a stationary observer

The length of the spaceship of 120m was measured at rest relative to the spaceship so we will take that as the proper length, dennoted L_proper
We first calculate the Lorentz factor:
Ɣ = 1/sqrt(1-(v/c)²)
Ɣ = 1/sqrt(1-0.85²)
Ɣ = 1.8986... (Keep this number in your calculator as rounding now will affect your final answer)
Now, relate this to the formula for length contraction:
L = L_{proper /} Ɣ
L = 120/1.8986...
L = 63.2m as measured by the stationary observer