Aprinter can print 27 pages in 4.5 minutes. how much time does it need to print 324 pages?

So if the printer can print 27 pages in 4.5 minutes, then how much time does it need to print 324 pages?
The equation looks like this:
4.5/27 = ?/324

To find the value of ? divide 324 divided by 27 which equals 12. Then multiply 12 x 4.5 because to keep the equivalent, you must do the same to the top as you did the bottom. 12 x 4.5= 54

So, to print 324 pages, 54 minutes is needed. 
4.5/27 = 54/324

I hope this helps:)