Arrange sequential order of constructing frequency table:
(i) Width of class interval
(ii) Range
(iii) Tally mark for each score
(iv) Number of class interval

Question

Arrange sequential order of constructing frequency table: 
(i) Width of class interval 
(ii) Range 
(iii) Tally mark for each score 
(iv) Number of class interval

Accepted Answer

The correct option is (3):
The sequential order for constructing a frequency table is correctly given by **(ii) Range**, **(i) Width of class interval**, **(iv) Number of class interval**, and finally **(iii) Tally mark for each score**. The process must logically begin with calculating the **Range (ii)**, which is the difference between the maximum and minimum values in the raw data; this step is fundamental because it establishes the total spread of the scores. Once the range is known, a statistician typically decides on the **Width of the class interval (i)**, often choosing a convenient size like 5 or 10. The width selection then dictates the **Number of class intervals (iv)** needed to cover the entire range (calculated as Range / Width). After the complete framework of class intervals is established, the final step is to go through the raw data and enter the **Tally mark for each score (iii)** to find the frequency of scores falling into each class. This systematic approach ensures all data is accounted for and classified properly.

The incorrect option is (1):
The sequence (i) (ii) (iv) (iii) is incorrect because it proposes determining the **Width of class interval (i)** before calculating the **Range (ii)**. Logically, you cannot accurately or meaningfully define the size of the class intervals until you know the overall spread of the data, which the range provides. The Range is the required input to ensure that the chosen class width and subsequent number of classes will adequately cover all data points from the lowest to the highest score. Placing the tallying step (iii) last is correct, but the initial order of the structural elements is flawed.

The incorrect option is (2):
The sequence (iv) (ii) (i) (iii) is incorrect because it starts with determining the **Number of class interval (iv)** before the **Range (ii)** is calculated. Like the explanation for option (1), the range is the most basic measure of spread and the essential first step in constructing a frequency distribution. You must first know the total ground to be covered (Range) before you can decide how many classes (Number of intervals) to divide it into or how wide the classes (Width of class interval) should be. The range is the mandatory prerequisite for defining the class structure.

The incorrect option is (4):
The sequence (i) (ii) (iii) (iv) is incorrect primarily because it inserts the **Tally mark for each score (iii)** as the third step, followed by the **Number of class interval (iv)**. Tallying marks is the act of classifying the data into the defined classes, and this can only be done *after* the entire framework of the frequency table has been established. This framework is defined by the Range, the Width, and the Number of Class Intervals. Consequently, tallying must logically be the very last step, as it depends on the preceding three parameters.