12:17:44 Sisi Nose: NELSON came up with the task... so that students (and their parents) would be more interesting to learn:
Ivan Sidorchuk's wife has a cycle of 28 days, and the critical days are 5 days, Ivan's mistress has a cycle of 2 days shorter, but it lasts 2 days less. The secretary tt. Sidorchuka critical days as in the wife, and the cycle as in the mistress. Question: What is the probability that today Ivan Sidorchuk can relax and drink a beer?