The course on statistics in 5th grade with the definition of frequency and the study of the histogram with calculations and grouping by class will be beneficial to you. The student should be able to study a statistical series and all the definitions concerning the population and the study of a quantitative or qualitative character. In addition, he will develop skills in calculating frequencies and percentages.
I. Numbers and statistical frequencies
When conducting a statistical survey, the set with which the survey is conducted is called
The theme of the survey is called character.
The latter can be quantitative (measurable) or qualitative (not measurable).
Thesize of one of the values of the characteristic, noted , is the number of times this value of the characteristic is repeated.
Thetotal number of people, noted N, is the sum of the numbers.
We have with p being the number of values of the character.
The frequency of one of the values of the character is the quotient of its number by the total number.
We have .
Students in a class were asked how many first names they have.
The total number of students is 30.
12 out of 30 students have two first names, so the frequency of students with two first names is :
- with a fraction.
- 0.4 with a decimal.
- 40% with a percentage.
II. grouping of data in classes
In the case of many numerical data, they can be grouped into classes to facilitate the presentation of numbers and frequencies.
A histogram is used to represent numerical data in the classroom.
When the classes have the same amplitude (continuous quantitative character), the heights of the bars of a histogram are proportional to the numbers (or frequencies) of each class.
The data from paragraph II are repeated.
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