Variable and Constant: A variable is something that can change, while a constant does not change. For example, workers may have different wages but a fixed conveyance allowance. Qualitative and Quantitative Variables: Qualitative variables observe the presence or absence of attributes and include things like student intelligence or hobby. Quantitative variables are measured by counting or measurements and include accidents, teachers, and temperatures. Discrete and Continuous Variables: Discrete variables are counted and include things like rooms or children. Continuous variables are measured and include heights, weights, ages, and temperatures.

1. NADEEM UDDIN
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OF STATISTICS
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2. Variable and Constant:
The word variable is used for something change from
person to person, place to place and time to time
otherwise it is a constant.
For example
Different workers may have different wages but their
conveyance allowance may be fixed.

3. Qualitative variable :
It is generated by observing the presence or absence of
some quality (attribute) in individuals.
For example
* Intelligence of a group of students.
* Hobby of a college teachers.
* Colour and texture of the material.

4. Quantitative variable :
A set of observations generated by counting or by
measurements is called quantitative data.
For example
* Number of accidents on roads.
* Number of teachers in colleges.
* Temperature in different cities.

5. Discrete Variable:
Discrete variable is generated by counting or
enumeration. It may also be called count variable. A set
of observations on discrete variable is called discrete
data.
For example:
* Number of rooms in any house
* Number of children in any family.
* Number of buttons on a shirt.

6. Continuous Variable:
A continuous variable is generated by measurements. It
may also be called a measure variable. A set of
observations on a continuous variable is called
continuous data.
For example:
* Height of a person.
* Weight of a person.
* Age of a person.
* Temperature of a city.
* The length of the sleeves.