# Notes Class 9 Mathematics Chapter 14 Statistics

Please refer to Statistics Class 9 Mathematics Notes and important questions below. The Class 9 Mathematics Chapter wise notes have been prepared based on the latest syllabus issued for the current academic year by CBSE. Students should revise these notes and go through important Class 9 Mathematics examination questions given below to obtain better marks in exams

## Statistics Class 9 Mathematics Notes and Questions

The below Class 9 Statistics notes have been designed by expert Mathematics teachers. These will help you a lot to understand all the important topics given in your NCERT Class 9 Mathematics textbook.

Refer to Chapter 14 Statistics Notes below which have been designed as per the latest syllabus issued by CBSE and will be very useful for upcoming examinations to help clear your concepts and get better marks in examinations.

1. Collection of Data
2. Presentation of Data
3. Graphical Representation of Data
4. Measures of Central Tendency
Statistics is the area of study that deals with the collection presentation, analysis and interpretation of data.
Data: Facts or figures, collected with a definite purpose, are called data.
There are two types of data (i) Primary (ii) Secondary
We can represent the data by (i) ungrouped and grouped frequency distribution.
Data can also represent by (i) bar graph (ii) Histogram (iii) Frequency polygons
Class mark of grouped data is lower limit + upper limit/2
Measure of central tendencies by mean, median, mode.

Median: Arrange the observations in ascending or descending order then if numbers of observations (n) are odd then then median is n+1/2 term.
If no. of observations (n) are even, then median is average of n/2th and n/21th + terms.
· Mode: The observation whose frequency is greatest.
• Mode = 3 median – 2 mean.