You know M(r) = v^2r /G

d = distance; s= speed
Planet 1: d=2/s=120
Planet 2: d=4/s=60
Planet 3: d=9/s=40
Planet 4: d=16/s=30
Planet 5: d=36/s = 20

You use the distance and orbital speed of the first planet to determine the mass enclosed within the orbit of the first planet to be 3 solar masses. Do the same thing for the other planets - determining the mass inside the orbits.Figure out how many times bigger/smaller the mass inside the second/third/fourth/fifth orbit is compared to the mass inside the first orbit.

2 answers

What is d? What is s?
d is distance and s is speed