- how too find class marks ??explain with an example ??
- wat is histogram , expalin with an example !?
- expain who to find scale with example !???
Class mark:
The mid-value of a class is called the class mark.
Consider a class interval 54.5 - 59.5, its class mark is find as:
Similarly class mark for any interval 110 - 120 is find as:
Histogram
They are used to show "continuous data", or the data that is distributed in small intervals within a certain range. For example, the histogram of number of students scoring the marks in a particular range is given below.
Here, the scored marks are distributed in the small intervals such as 0-10, 10-20, 20-30, 30-40 and 40-50 within the range of 10 marks.
Choosen Scale:
The scale is choosen as per the data given. For example, consider the data shown below
Class interval | Frequency |
2.0−2.5 2.5−3.0 3.0−3.5 | 6 4 5 |
In this case we will choose the scale x-axis starting from 1.5 followed by every interval more than 0.5 the previous one.
Consider an another example as:
Class interval | Class mark | Frequency | Points |
300−350 350−400 400−450 450−500 500-550 | 325 375 425 475 525 | 5 10 17 20 3 | A (325, 5) B (375, 10) C (425, 17) D (475, 20) E (525, 3) |
Here, the scale on x-axis is taken from 275 followed by every value more than 50 than the previous one.
Hope you get it!!