Double (overlapping) separable verbs?
What I can tell you is that this kind of structure is to express emphasis.  



'她惊讶得说不出话来' has the same meaning as '她惊讶得话都说不出来'.
But the latter uses the inverted pattern, which is always used as for emphasis.  



'说话' and '出来' in this kind of situation do not overlap. What's more, '出来' stresses the act of speaking.
It may be translated as 'I even can't work this simple question out.'  



If you still don't understand, don't hesitate to ask.