1. The problem statement, all variables and given/known data here's the question , Part of solution was given , but not the final ans . I have tried to do , but i need someone to verify my ans . 2. Relevant equations 3. The attempt at a solution Since , stress of steel is 12.5 times of stress of concrete . The max allowable stress in steel is 175MPa , while for the concrete is 20MPa . The author choose stress of steel = 175MPa , because by doing so , the stress in concrete is 14MPa(<20MPa) , But if the author choose stress of concrete = 14MPA , then the stress of steel would be = 12.5(14) = 250MPa , which is (>175MPa) So , in 2nd part , my working = (17.5x10^6)(Area of steel) + (14x10^6)(10 Area of steel ) = 1000x10^3 so , Area of steel = 0.52(mm^2) , is my ans and concept correct ?