A student has three methods of solving a problem. It takes him 1 hour to solve the problem using method A. It takes him 45 minutes to solve the problem using method B. It takes him 30 minutes to solve the problem using method C. His friends discovered that the student uses method A 10% of the time, method B 40% of the time, and method C 50% of the time. What is the expected time it takes the student to solve a problem?