Sue worked 7 1/3 hours on wednesday and 4 1/2 hours on thursday. how many more hours did she work on wednesday than thursday?

Plz me i need i will give a brain

Does the problem involve permutations or? combinations? do not solve. the matching section of an exam has 4 questions and 7 possible answers. in how many different ways can a student answer the 4 ? questions, if none of the answer choices can be? repeated?

How do you solving the solution of each system using elimination?