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Detailed solution to a problem of mathematical statistics and probability in senior high school
The answer process is as follows:

The first question is to find the value of m, and the heights of the four small rectangles on the left given in the question form a geometric series with a common ratio of 2 from left to right. So suppose the height of the first small rectangle is a 1, the second is a 1×2, the third is a 1× 2 2, the fourth is a/kloc-0 /× 2 3, and the fourth is m, then a1can be obtained.

Then according to the frequency histogram, the area of each small rectangle adds up to 1, and the value of m is 0.032.

The second question is the average score of the written test, which is the average score. The average value of the frequency histogram is equal to the area of each small rectangle multiplied by the midpoint of each set of abscissas. Therefore, according to the obtained data, the average value can be calculated as 67. 1.

The third problem is to estimate the admission score. First of all, find the admission rate, that is, 600/2000=0.3. That is, applicants with the highest score of 30% should be admitted.

According to the frequency histogram. 80- 100 and above account for 20% of the total, and 70- 100 and above account for 40% of the total, so the admission score should be between 70 and 80. So let the admission score be x, then (80-x)/(80-70) × 0.2+0.15+0.05 = 0.3. Solve x = 75.