Are you sure that was the exact number for the mbps questions? Because I got 7.4 not 57.43. Do you have the multiple choice paper?
So the question was 'an internet connection has a download speed of 16.8 megabits per second. Approximately how long would it take to download a 120.6 megabyte video file?'
The purpose of the question was to see if you knew the difference between bits and bytes - since they're two different things. A byte is the same as 8 bits, so before you can do any division you have to convert something so they're both the same unit of measurement - just times the megabytes by 8, or divide the megabits by 8, either will work. Then just divide the file size by the download speed and you get the answer.
So the working out is:
120.6x8=964.8
964.8/16.8=57.42857...
=57 (C)
Or you could do:
16.8/8=2.1
120.6/2.1=57.42857...
=57 (C)
What it sounds like you did was just divide the size by the speed straight up,
120.6/16.8=7.17857...
=7 (A)
but that's incorrect because the units of measurement are different and you gotta convert something first so they're the same.
Same with Q10, 50GB is actually 50x1024 megabytes, not 50x1000 as is commonly believed.
(50x1024)/1.8=28444.44444...
=28444 (C)
I wrote a page and a half for the last question, but I've got pretty small writing (around 13 words per line). If the example answers from past papers are anything to go by, you're not gonna need most of that to earn the full marks... doesn't hurt to have extra just in case though, specially with so much time to go back and look over answers :L