The photocopying rates of two machines C and D are as shown. Both machines were use to make a copy of a set of notes which had been divided into teacher set and student set. Machine C took 3 minutes is to photocopy teacher set and Machine D took 4 minutes to photocopy student set.
- How many pages were there altogether in the set of notes?
- Another copy of the same set of notes was made using Machine D only. How many minutes did Machine D take?