Space probe, planet, and sun..... Correcting test again, and I don't know where to start on this problem: A space prob lies along a line between a planet and the sun so that the sun's gravitational pull on the probe balances the planets pull. The distance of the probe from the planet is 1.0 x 10^11m. The distance between the planet and the sun is 1.5 x10^12m. Find the mass of the planet. Mass of the sun = 2x10^30kg. I got 0/15 on this problem so nothing I put down was right....help???