"Frequency Histogram" PPT courseware

Description

"Frequency Histogram" PPT courseware

learning target

1. Understand the concept of frequency histogram;

2. Able to read frequency histograms;

3. Be able to draw frequency histograms.

Reflection

1. In statistics, we call the number of occurrences of each object under examination _______, and the ratio of the number of occurrences of each object to the total number of occurrences is _____.

2. The sum of the frequencies of each object is equal to ________, and the sum of the frequencies of each object is equal to _____.

3. It is known that in a sample, 50 data fall into 5 groups respectively. The numbers of the first, second, third and fifth data are 2, 8, 15 and 5 respectively. Then the frequency of the fourth group is _____ , the frequency is _____.

Knowledge explanation

Example: The results of a math test in a certain class are as follows:

63, 84, 91, 53, 69, 81, 61, 69, 91, 78, 75, 81, 80, 67, 76, 81, 79, 94, 61, 69, 89, 70, 70, 87, 81, 86, 90, 88, 85, 67, 71, 82, 87, 75, 87, 95, 53, 65, 74, 77.

What score range do most students fall into? What is the overall distribution of grades?

General steps for drawing a frequency histogram:

(1) Calculation range: 95-53=42 (minutes)

(2) Determine the group distance and number of groups.

Range/group distance=42/10=4.2

The data is divided into 5 groups.

(3) Decide on points.

49.5~59.5, 59.5~69.5,

…89.5~99.5

(4) Column frequency distribution table.

(5) Draw a frequency distribution histogram.

The horizontal axis represents each group of data, and the vertical axis represents the frequency. If the frequency within the group is high, a rectangle is drawn.

Track training

Calculate the frequency histogram of the number of rope skipping times per minute for several eighth-grade students at a time. Please answer the following questions based on this histogram:

⑴ What is the total number of people participating in the test?

⑵ What is the frequency and frequency of the last group from left to right?

⑶ When grouping data, what is the group interval?

little analyst

If the visual acuity is below 4.85, it is considered abnormal. Then please analyze the visual acuity situation in our school. When you see this situation, what do you want to say to the students around you?

Practice in class

Randomly check the number of pulse beats per minute of 20 students and obtain the following data (unit: times):

81 73 77 79 80 78 85 80 68 90

80 89 82 81 84 72 83 77 79 75

Please make a frequency distribution table for the above data.

Summary of this lesson

General steps for drawing a frequency histogram:

(1) Calculate the difference between the maximum value and the minimum value and determine the range of the statistics;

(2) Determine the number of groups and the distance between groups;

(3) Determine the points;

(4) Column frequency distribution table;

(5) Draw a frequency histogram.

Keywords: Frequency histogram teaching courseware, Qingdao edition ninth grade mathematics volume 2 mathematics PPT courseware download, ninth grade mathematics slide courseware download, frequency histogram PPT courseware download, .PPT format;

For more information about the "Frequency Histogram" PPT courseware, please click the "Frequency Histogram ppt" tab.

"Frequency Histogram" PPT courseware 2:

"Frequency Histogram" PPT Courseware 2 General steps for drawing a frequency distribution histogram: (1) Calculate the difference between the maximum value and the minimum value, and determine the range of statistics; (2) Determine the number of groups and group distance; (3) Determine the score points; (4) column frequency distribution table; (5) draw frequency..

File Info

Update Time: 2024-06-27

This template belongs to Mathematics courseware Qingdao Edition Ninth Grade Mathematics Volume 2 industry PPT template

Preview