plaverbach - Some hard questions may take up to 3 minutes to solve. Please understand that 2 min is only an average time to solve each question on the GMAT. In fact, you may take up to 3 minutes to solve even a sentence correction question. When you are at a learning phase, the best strategy is to grasp the concepts rather than solve questions in a stipulated time. That said, you should never cross the 4 min mark on a single question; if you encounter a question that takes more than 4-5 min to solve, please realize that you must be doing something wrong; GMAT is a test of logic, so it is likely that there's a much simpler and 'logical' way to approach the same question.