2023 Author: Bryan Walter | [email protected]. Last modified: 2023-05-21 22:24
Singaporean TV presenter Kenneth Kong posted a math problem on his Facebook page, noting that in their country it is a question for fifth graders. The problem that has puzzled thousands of Internet users is formulated as follows.
Albert and Bernard just met Cheryl. "When's your birthday?" - Albert asked Cheryl. Cheryl thought for a second and said: "I won't tell you, but I will give you some hints." She wrote a list of ten dates: May 15 - May 16 - May 19 June 17 - June 18 July 14 - July 16 August 14 - August 15 - August 17 “One of these dates is my birthday,” she said. Sherrill then whispered in Albert's ear a month - only a month - in which her birthday is. She whispered a number to Bernard, and only a number. "Can you guess now?" she asked Albert. Albert: I don’t know when your birthday, but I know that Bernard doesn’t know either. Bernard: At first I didn’t know, but now I know. Albert: Well, now I also know! When is Cheryl's birthday?
Later it turned out that this is not a problem for fifth-graders, but for a mathematics Olympiad in high school. Nevertheless, many had difficulties with its solution. Kenneth Kong was even approached by the organization that compiled this problem for the Olympiad, with a request to clarify the situation with the fifth graders so that parents would not be horrified that their child could not solve the problem from the compulsory program.
As a result, the Cheryl problem became a phenomenon similar to the color of the dress, although not on such a large scale.
