Physics
posted by Sierra .
Uranus makes one complete orbit of the Sun every 83.8 years. Calculate the radius of the orbit of Uranus. Hint: It is a very good approximation to assume this orbit is circular.

Try G*Ms*Mu/R^2 = Mu*Vu^2/R
here Ms = mass of Sun
Mu = mass of Uranus
Vu = Speed of Uranus
R =Orbital radius
Also 2*pi*R = Vu*T will give value of Vu which when plugged in the first equation will give R.