You can
put this solution on YOUR website!with this type of question, the hardest bit is converting the english into maths, so we have to step through it carefully.
First, lets define a couple of things we are looking for:
Let x = number of large font pages.
let y = number of small font pages.
Look at the english...he uses a number of large font pages and some small font pages. The total number of words is 48000.
So...how many large font words does he use? Well,
on 1 page... 1800
on 2 pages... 2*1800
on 3 pages... 3*1800
so
on x pages... x*1800 --> we write this as 1800x
Similarly, how many small font words does he use? Well, again...
on 1 page... 2400
on 2 pages... 2*2400
on 3 pages... 3*2400
so
on y pages... y*2400 --> we write this as 2400y
So, the total has to be 48000, ie

. This is equation 1.
Now we need another equation. The only other bit of info is that the total number of pages = 21.
Well, we know he uses x large print pages and y small print pages, so:

is equation 2
Now you have 2 equations, 2 unknowns...you can solve them simultaneously. Have a go. Answer is x=4, y=17
cheers
Jon.