Different types of Story Problems

First graders have been working on two different types of story problems during our first math unit.  They have been paying close attention to the information that a story problem gives them.  In some cases, they have noticed, the problem gives the parts and they need to determine the whole (or total), while in other cases the problem gives the whole (or total) and they must figure out the possible parts to make that whole.  Because of this, some problems have only one possible solution, while other problems have more than one possible solution.