1. The problem statement, all variables and given/known data To determine the location of her center of mass, a physics student lies on a plank of weight 100.0 N and length 2.5 m supported by two scales 2.50 m apart. The left scale reads 420.0 N, and the right scale reads 210.0 N. (Note: Don’t neglect the weight of the plank when you do this problem.) a. Find the student’s weight.  b. Find the distance of her center of mass from the left scale (x=0).  2. Relevant equations T = rF Wgirl = 420 + 210 3. The attempt at a solution I get her weight as 630 N. But when I go to solve for the distance using center of mass, when I place the point of rotation at the left support I get her center of mass as .635 m from the left side, but using the right support, I get her center of mass as 1.47 m away from the right side or 1.03 m from the left side. What am I doing wrong to get two different center of masses.