Class 11 Mathematics — Chapter 13: STATISTICS
Chapter 13: STATISTICS is a chapter in Class 11 Mathematics (NCERT), part of the CBSE NCERT curriculum followed by over 25 million students across India. This chapter covers 6 topics including Measures of Dispersion vs. Central Tendency, Range, Concept of Mean Deviation. BrainWeave provides free AI-powered explanations — by voice or text, in Hindi or English — with no signup required.
What you'll learn
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▸Measures of Dispersion vs. Central Tendencydispersionvariabilitycentral tendencyspreadscatter
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▸RangeCore conceptrangemaximum valueminimum valuevariability
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▸Concept of Mean DeviationCore conceptmean deviationabsolute deviationcentral valueM.D.(a)
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▸Mean Deviation about the Mean for Ungrouped DataCore conceptmean deviation about meanungrouped dataarithmetic mean|xᵢ – x̄|M.D. (x̄)
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▸Mean Deviation about the Median for Ungrouped DataCore conceptmean deviation about medianungrouped datamedian|xᵢ – M|M.D. (M)
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▸Mean Deviation for Discrete Frequency DistributionCore conceptdiscrete frequency distributiongrouped datafrequencyΣfᵢ|xᵢ – x̄|N
Chapter Summary
Understand why measures of central tendency like mean and median are insufficient to describe a dataset, and recognize the need for measures of dispersion to quantify the spread or variability of data.
Define and calculate the range of a dataset as the difference between the maximum and minimum values, and understand its limitations as a simple measure of dispersion.
Understand the concept of mean deviation as the mean of the absolute values of deviations from a central value (mean or median). Recognize why absolute values are necessary.
Calculate the mean deviation about the arithmetic mean for a set of individual observations (ungrouped data) by finding the mean of the absolute deviations from the data's mean.
Calculate the mean deviation about the median for a set of individual observations (ungrouped data) by finding the mean of the absolute deviations from the data's median.
Calculate the mean deviation about the mean for data presented as a discrete frequency distribution, using the formula that incorporates the frequencies of each observation.
Practice Questions from this Chapter
Tap "Get Solution" on any question to ask our AI tutor.
- Explain data variability simply. Get Solution →
- Give real-world examples of mean. Get Solution →
- Compare mean and median uses. Get Solution →
- What are the three measures of central tendency mentioned in the text? Get Solution →
- How is the Range of a data series calculated? Get Solution →
- According to the text, what is the value of the sum of the deviations from the mean (x̄)? Get Solution →
- A 'measure of dispersion' is a single number used to describe what property of data? Get Solution →
- What is the first step in calculating the mean deviation about the mean for ungrouped data? Get Solution →
Did you know?
- 💡 The word 'statistics' comes from the Latin 'statisticum collegium', meaning state council.
- 💡 Ancient Egyptians used statistics to predict the annual flooding of the Nile River.
- 💡 The world's longest running statistical study has continued non-stop since 1938.
- 💡 A chicken lays an average of 300 eggs per year, but some lay none.
- 💡 You are more likely to get struck by lightning than win the lottery jackpot.
Frequently Asked Questions
How many topics are covered in this chapter?
This chapter covers 6 key topics: Measures of Dispersion vs. Central Tendency, Range, Concept of Mean Deviation, Mean Deviation about the Mean for Ungrouped Data, Mean Deviation about the Median for Ungrouped Data, and more. The BrainWeave AI tutor explains each one with examples.
Is Chapter 13: STATISTICS important for board exams?
Class 11 is a foundation year. Mastering this chapter now will help you build strong fundamentals for the higher classes.
Can I get NCERT solutions for this chapter in Hindi?
Yes. BrainWeave's AI tutor supports Hindi, English, and Hinglish for both voice and text chat. Just ask your question in your preferred language.
Is BrainWeave free for Class 11 - Science?
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Can I use voice chat for this chapter?
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