Those are pretty challenging problems and they also require a bit of working out. How many of these problems are students expected to solve in, say, and hour long test?
These two are straight-forward problems, both will be allocated some basic nominal time. You either know how to solve them or you don't. Sometimes there'd be problems that are more puzzling, because they'd combine several problem classes and will take time to unfold (this is typical in math olympics). These will be allocated more time as they require thinking and searching for a solution.