(2006? Jingzhou) A middle school combined with the moral education plan of "Eight Honors and Eight Disgraces" and launched a keynote speech contest of "Be Honest". The timetable is divided into "prepa

(2006? Jingzhou) A middle school combined with the moral education plan of "Eight Honors and Eight Disgraces" and launched a keynote speech contest of "Be Honest". The timetable is divided into "preparatory stages" (1) The degree of central angle corresponding to "the number of people with 90 points or more" in the ninth grade preliminary round:

200÷(40+ 180+300+200)×360 = 100 ;

(2) When the number of people over 90 years old in the eighth grade preliminaries is 1.5% = 200, just fill in the map;

The number of participants in the school's preliminaries =600+620+720= 1940 (person);

So the answer is: 1940 people;

(3) The model of the seventh grade is 8 1 (points); The median of the eighth grade is 86 (points); The average score of grade nine is 85 (points);

(4) strive for personal first. The seventh grade is the strongest, because the highest score in the semi-finals is in the seventh grade.

If you look at the total score (or average score), the ninth grade is the strongest, because three people are selected for the rematch in each grade, and one player is in the seventh grade, with a rematch score of 999 1.89 and an average score of 93; The average score of three players in the eighth grade rematch in 97, 88 and 88 is 91; Three ninth-grade players in the semi-finals of 97, 96 and 89 scored an average of 94 points.