Users of the popular British forum for parents, Mumsnet are unable to solve the problem, intended for elementary school students. Example published by the user under the name lucysmam.
The woman asked other visitors to help with the sample solution, which she was unable to cope on their own.
“On the coast of the three lighthouse. The first shines for three seconds then it turns off for three seconds. The second lit and four seconds and off for four seconds. The third Shine for five seconds, then it shuts down for five seconds. When was the first time all three of the lighthouse will be simultaneously disabled and when they both light up?” these are the conditions of the problem. Woman found it in a textbook for eight year-olds.
The question seemed to users is so complex that many parents were in disbelief. Some are unable even to assume, how can this problem be solved. “This is a ridiculous question, and I’m only here in order to find out the answer,” said one of the visitors.
In the end, users have begun to draw graphs and create formulas to find the correct answer. According to most techies, all the beacons will be turned off in six seconds, and be operated simultaneously in 120 seconds. However, the decisions were few, so visitors to the forum and have not come to a consensus.
Video, photo All from Russia.