1. The problem statement, all variables and given/known data 2. Relevant equations δ = Pl/AE σ = P/A 3. The attempt at a solution I had calculated the deformation for both the steel and aluminum, and added them together to give me δ = 0.481 mm, which is incorrect. I also thought I could simply plug in the force P = 200kN and the respective cross sectional areas for each material into the stress formula, which also gave me incorrect answers. Not sure where to go from here.