Mathematics textbook for 5th grade. According to the terms of the problem, every day a Pedestrian leaves from point “A” to point “B”, and on the way he meets a Cyclist. Then he returns home, where his faithful wife is waiting for him. The next day everything repeats itself. But one day the Pedestrian is stopped by the Investigator and reports that the Cyclist has disappeared. The investigator asks the Pedestrian to go with him to point “B” to interview witnesses and together figure out this complicated story.
