A printing press is printing brochures. The press prints 20 single-page spreads, and twice as many double-page spreads. For each 4 pages printed for the spreads, the press prints a block of 4 ads, each of which take up a quarter of a page. The brochures can be arranged in any order as long as they are made up of 5 pages each. How many brochures is the printing press creating? Let's think first. Chain of thought:
There are a total of 20 single - page spreads * 2 = 40 double - page spreads. As these are made up of 2 pages each, there are 40 double - page spreads * 2 pages = 80 pages in the double - page spreads. In total, there are 20 single - pages + 80 double - pages = 100 pages in the spreads. A block of ads is printed every 4 pages, so there will be 100 pages / 4 pages / block = 25 blocks of ads. This is a total of 25 blocks * 4 ads = 100 ads. As each ad takes up a quarter of a page, this must create an additional 100 ads * 0.25 = 25 pages. Therefore, the press has printed 100 pages from the spreads + 25 pages of ads = 125 pages. Since brochures are made up of 5 pages each, this creates a total of 125 pages / 5 = 25 brochures.
Therefore, the answer is 25.