hi I've this doubt. If the number of ads in a page is 3, then is the earnings per click less than that when the number of ads in that page is 1. I am newbie to adsense. So i'm not sure about these things.
No, number of ads displaying on a page is never a criteria to determine the earnings per click, it depends on many factors which are dependent of the quality of the content of the page and the traffic.
earning depends on ctr + effectiveness of ad unit so if more ppl r clicking on 2 ad unit that earnings will be high. for link unit ur reader should leave u clicks but sometime they give good ctr. i only use ad unit 2 large / medium rectangler + large skyscraper is good avoid using banner they pay less.
Its also Takes Effect If u have a Right Ads on Right place Coz some of Ads Content give more revenue Like large rectangle .. so try out with Good traffic .. coz Real visitor will gives u only Revenue