Key issues: determine the initial position of the minute hand and the hour hand, and determine the distance difference between the minute hand and the hour hand.
Grid method: divide the circumference of the clock face into 60 grids evenly, and each grid is called 1 grid. The minute hand walks for 60 minutes every hour, which is a week; The hour hand only moves for 5 minutes, so the minute hand moves 1 minute, and the hour hand moves112 minutes.
Degree method: from the angle, the circumference of the clock face is 360, the minute hand turns 360/60 degrees per minute, that is, 6 degrees, and the hour hand turns 360/ 12*60 degrees per minute, that is, 1/2 degrees.
International Mathematical Olympiad. The name of "Mathematical Olympics" originated from the Soviet Union, which is related to sports competitions, the birthplace of science, ancient Greece and mathematical competitions.
In the first half of the 20th century, different countries organized all kinds of mathematics competitions at all levels, first in schools, then in regions, and then in the whole country, and gradually formed a pyramid competition system. The further development of national competitions naturally creates the necessary conditions for the formation of the highest level international Olympic competition.
1994, the American Olympic team set an excellent score of six people in IMO history for the first time. On July 5, 2022, the final result of the 63rd IMO in 2022 was announced. China's six players got full marks, and China won the first place in the team total score with 252 points.