Class 11 Math: Statistics Quick Revision Chapter Summary
Need to review the entire chapter before a test? This quick revision guide summarizes all the core concepts, topics, and equations taught in Class 11 Statistics to help you refresh your memory instantly.
Core Topics At a Glance
### š Range and Mean deviation for ungrouped/grouped data Range is the difference between the maximum and minimum values. Mean deviation measures the average of the absolute differences between each data point and the mean (or median).
### š Variance calculation Variance measures the spread of data. It is the average of the squared deviations from the mean, which gives more weight to extreme outliers.
### š Standard deviation of grouped data Standard deviation is the positive square root of the variance. It measures the spread of data in the same units as the original data points.
### š Coefficient of variation The Coefficient of Variation (CV) is a dimensionless measure of relative variability. It is calculated as the ratio of standard deviation to the mean, expressed as a percentage. It is used to compare consistency.
Key Formulas Mind Map
- Grouped Variance: `\sigma^2 = \frac{\sum f_i(x_i - \bar{x})^2}{N}` - Variance of grouped frequency distribution....
- Standard Deviation: `\sigma = \sqrt{\sigma^2}` - Square root of variance, measuring dispersion in original units....
Revision Checklist
- Review the subtopic guides and outline notes.
- Practice writing the key formulas from memory.
- Solve at least 3 worked examples and check your steps.
- Take a timed practice quiz to verify your speed.