1. The problem statement, all variables and given/known data "A uniform plank, length of 4M,has a mass of 120N and rests on top of two stools. One Stool, A, is 0.5M into the plank on the left side. The other stool, B, is 1.0M in on the right side. An 80N weight is placed between the two stools. Find the Force upon stools A and B. Thus meaning that the 80N weight is 1.75M in on the left hand side, and 2.25 M in on the right hand side. 2. Relevant equations Moment of a force = Force * distance. 3. The attempt at a solution First I find the moment of the force of both A and B. A = (1.5M * 120N) + ( 1.25M * 80N) = 280 N m. B = (1m * 120) + (1.25M * 80) = 220N So, we now have a ratio of 280/500:220/500 = 0.56:0.44 0.56 * 200 = 112, and 0.44 * 200 = 88. Therefore, A = 112N and B = 88N. This seems all well and good, except according to my answer book it is the other way round. A should be 88 and B 112. I can't see where I've gone wrong. I'm thankful for any help given, I get so annoyed when I can't figure out a question =/.