To find the total area available for printing, we need to subtract the area of the margins from the total area of the pages.

The total area of the pages can be calculated by multiplying the length and width of each page and then multiplying by the number of pages: Total area of pages = (20 cm - 2.5 cm - 2.5 cm) * (14 cm - 2 cm - 2 cm) * 360 pages = 15 cm * 10 cm * 360 pages = 5400 cm² * 360 pages = 1944000 cm²

The total area of the margins can be calculated by multiplying the width of the margins by the perimeter of each page and then multiplying by the number of pages: Total area of margins = (2.5 cm + 2.5 cm) * (20 cm + 14 cm) * 360 pages = 5 cm * 34 cm * 360 pages = 61200 cm² * 360 pages = 22032000 cm²

Therefore, the total area available for printing is: Total area available for printing = Total area of pages - Total area of margins = 1944000 cm² - 22032000 cm² = 51840 cm²