For each click, advertisers appearing on the sites donate a set amount of money to selected projects. While some site advertisers contribute additional funds if consumers visit or buy from them, no purchases are necessary to make a difference. Clicking alone helps the needy. Advertisers benefit because they get their names associated with worthwhile causes. Each site explains its project in detail, which is a helpful way to learn about problems around the world.
Visitors can only contribute one click per cause per day, a system that is monitored by computers.
At the bottom of the site, there are several running meters, one that counts the human population, another that tracks natural habitats, and a third that monitors natural habitats per capita. In the year 2000, the Rainforest Site received 15,559,026 clicks, which saved 204,923,061 square feet of land. Based on these figures, estimate how much each click is worth in terms of square feet. Round the numbers up or down to make the task easier. Riverdeep's Destination Math MSC III course, Ordering and Rounding Whole Numbers, can help.