The transformed-section method will be used to analyze the composite bar. The following steps will be needed:
1) Compute the modular ratio n. For this problem, the stiffer material (brass) will be transformed into an equivalent amount of the less stiff material (aluminum).
2) Transform the brass bar (2) into an equivalent amount of aluminum (1). Multiply its dimension parallel to the axis of bending (the z axis for this problem) by the modular ratio.
3) Compute section properties for the transformed cross section.
4) Use the allowable stresses to determine which material controls the bending capacity of the composite bar.