Frequency of group scores
1 47.5~59.5 2 0.05
2 59.5~7 1.5 4 0. 10
3 7 1.5~83.5-0.2
4 83.5~95.5 10 0.25
595.5 BC ~107.5 BC
6 107.5~ 120 6 0. 15
Total 40 1.00
Answer the following questions according to the information provided in the table:
A=, b=, C = in (1) frequency distribution table.
(2) There are 50 classes in the whole school (40 students in each class on average). If the score above 108 is excellent, please estimate that the number of excellent students in this mock exam is about.
(3) Complement the histogram of complete frequency distribution and display the basket of analysis questions. 2. In order to know about the subjects of the final examination of 800 eighth-grade students in our district 15000, the mathematical scores of 800 students were selected for statistical analysis. Then the following judgment is correct ().
A. this kind of survey is a general survey.
B. 15000 students are the population.
C. Every student is an independent individual.
The math scores of d. d. 800 students are the overall sample.
Display analysis test basket 3. Xiaoqing's eighth grade math scores in the last semester are as follows.
Usually, mid-term exams and final exams
Score 86 90 8 1
If you calculate the term total score according to the weight in the picture, Xiaoqing's term total score is points. 4. The usual grades, mid-term grades and final grades of three eighth-grade students in a school are as follows:
Mid-term and final period at ordinary times
Student A 90 95 85
Student B 90 85 95
Student C 80 90 97
(1) Calculate the average score of three people respectively. Who has the best average score?
(2) According to the "importance" of the three grades, the teacher calculated the average score of the three students according to the proportion of 30%, 30% and 40% in the usual, mid-term and final grades respectively. According to this method, whose average score is good 5.J8minmanke Middle School has two copiers, A and B, which are used to print study materials and test papers. In the final exam of the seventh grade in school, the math test paper is copied by photocopiers A and B for 50 minutes and 40 minutes respectively. In order to keep the exam secret, it is not allowed to print the test paper prematurely. Decided to use two photocopiers to copy at the same time before the exam. After copying for 20 minutes, the B machine is out of order, and there are still 8 minutes before the papers are issued. Please calculate. 6. The math scores of a classmate in the eighth grade last semester were tested in the following table.
Category average time period
At the end of the exam
check
Test 1 Test 2 Test 3 Test 4
Score1101059511012.
(1) Calculate the average score of this classmate last semester;
(2) If the overall grade of the semester is calculated according to the weight shown in the pie chart, ask him what his overall grade was last semester. ☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆973
Jaco wants to know the growth of fish in the fish pond he contracted; ② Understand the number of SARS patients in China;
(3) Evaluate the final exam results of Grade 8, Class 10; Zhang Hong wants to know the taste of a pot of soup cooked by her mother. ☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆☆9
A. 1
four
B. 1
2
C. 1
nine
D.2
nine
The analysis test basket 9 is displayed. 2,000 test papers were randomly selected from120,000 test papers in the city, of which 1200 test papers were qualified. Accordingly, it is estimated that the number of qualified math scores in the city is. Display analysis test basket 10. Jinshi Middle School has two copiers, A and B, which are used to print study materials and test papers. The school held a final exam. It takes 90 minutes and 60 minutes to copy the math test paper with photocopiers A and B respectively. For the sake of confidentiality, the school decided to use two photocopiers to copy the test paper at the same time before the exam.
(1) Two copiers copy at the same time. How many minutes does it take to finish printing?
(2) After copying for 30 minutes, the B machine is broken and cannot be copied for the time being. At this time, there are still 13 minutes before the paper is issued. Please calculate, if the rest of the copying tasks are completed by machine A alone, will it affect the examination on time?
(3) After emergency repair, machine B was repaired and put into use again after 9 minutes. Please recalculate. Can the school hand out the examination papers on time?
1 1. There are 45 students in Class 7 (2) who took the final exam, and 42 of them passed. The probability of failure in drawing a test paper is 12. Xiaohua's math scores in the eighth grade last semester are shown in the following table:
Normal terminology of test category
At the end of the exam
check
Test 1 Test 2 Test 3 Project Learning
Achievement 88 70 98 86 90 87
(1) Calculate Xiaohua's average grade this semester;
(2) If the total evaluation score of this semester is calculated according to the weights shown on the right, please calculate Xiaohua's total evaluation score of this semester. The analysis test basket is displayed in 13. A school stipulates that students' math final evaluation score consists of three parts, of which 25% usually participate in math group activities and 35% finish homework. The final exam score accounts for 40%. Xiaoming scored 84 points in math activities, 92 points in homework and 88 points in the final exam, so the final evaluation score of Xiaoming's math is to understand the math situation of the senior high school entrance examination in our city, and take out the math papers of 2000 candidates for analysis. The math scores of 2000 students are this problem ().
A. Group B. Individual C. Sample D. Sample size
The analysis test basket is displayed in 16. Chongqing Nankai Middle School Grade 20 13 Grade 7 (Grade 1) Mathematics Final Exam officially started at 9: 00 am on 20 1 1 year/month 2 1. At 9 o'clock on the clock, the position relationship between the hour hand and the minute hand is. The analytical test basket is displayed at 65438.
85-86
Analysis test basket 18. The final scores of students in Grade 8 (1) class 10 are as follows: 80, 86, 86, 87, 88, 89, 89, 95. The pattern of these scores is ().
85-86
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Hope to adopt,