There are two students. The first,James, will be happy if he solves two problems in a row correctly, the second, Sam, will be happy if he solves the problem correctly only after an incorrectly solved problem. How many days in average James will wait for the "happiness" more than Petya? The probability of correctly and incorrectly solved problems is equal. At first glance, it seems that the answer is 0, since the probabilities are equal, but is this true? Don't think that this task solvesthat easily..