1. The problem statement, all variables and given/known data A mass attached to a holder hangs from a spring. the combined mass of the hanger, spring, and mass=45g. Adding mass of 55g stretches the spring 12cm. What is the spring constant? 2. Relevant equations Hooke's Law F=kx 3. The attempt at a solution (m1+m2)g/x=k (.045kg+.055kg)9.8m/s^2/m = k but this isn't right, I don't think. I'm not sure what I'm missing, but it seems that I don't have all the information correctly utilized. Hooke's law, though, is the only thing I could think to use with the given information and based upon what we need to find. any help would be greatly appreciated, as I need this information for my laboratory experiment.