🎯 Knowledge Check
Maths — STATISTICS
Share this Chapter
Found this helpful? Share this chapter with your friends and classmates.
💡 Exam Tip: Share helpful notes with your study group. Teaching others is one of the fastest ways to reinforce your own understanding.
Frequently Asked Questions
Statistics is the branch of mathematics that deals with the collection, organisation, presentation, analysis, and interpretation of numerical data.
Statistics helps in understanding trends, making comparisons, predicting outcomes, and taking data-based decisions in real-life situations.
Data refers to numerical information collected from observations, surveys, or experiments for analysis.
Raw data is unorganised data collected directly from a source without any classification or arrangement.
Grouped data is data organised into class intervals to simplify analysis when observations are large in number.
It is a table that shows how often values occur within defined class intervals.
Class intervals are divisions of data into fixed ranges used to group observations.
Class width is the difference between the upper and lower limits of a class interval.
The class mark is the midpoint of a class interval, calculated as \((\text{upper limit} + \text{lower limit})/2\).
Measures of central tendency describe a central or typical value of data, such as mean, median, and mode.
Mean is the average value of grouped data calculated using class marks and frequencies.
\(\bar{x} = \frac{\sum f_i x_i}{\sum f_i}\), where \(x_i\) are class marks and \(f_i\) are frequencies.
It is a method to calculate mean by assuming a convenient value as the mean to simplify calculations.
A short-cut method of finding mean using deviations divided by class width to reduce computation.
It is preferred when class intervals are equal and numbers are large.