NCERT Solutions Class 10 Maths Chapter 13 — Statistics#

Chapter 13 builds on earlier statistics by dealing with grouped data. You will calculate the mean using the direct method, assumed mean method, and step-deviation method, find the mode and median of grouped frequency distributions, and interpret cumulative frequency graphs (ogives).

exercise 13.1 exercise 13.2 exercise 13.3

Exercises#

  • Exercise 13.1 — Mean of grouped data (direct, assumed mean, step-deviation methods) (9 questions)
  • Exercise 13.2 — Mode of grouped data (6 questions)
  • Exercise 13.3 — Median of grouped data (7 questions)

What you will learn#

  • The mean of grouped data by the direct, assumed-mean and step-deviation methods.
  • The mode of grouped data.
  • The median of grouped data using cumulative frequency.

Key formulas and results#

  • Mean: $\bar{x} = \dfrac{\sum f_i x_i}{\sum f_i}$.
  • Mode: $l + \left(\dfrac{f_1 - f_0}{2f_1 - f_0 - f_2}\right) \times h$.
  • Median: $l + \left(\dfrac{\frac{n}{2} - cf}{f}\right) \times h$.

Read and revise#

Frequently asked questions#

How many exercises are in Class 10 Maths Chapter 13?
Three: Exercise 13.1 (9 questions), Exercise 13.2 (6 questions) and Exercise 13.3 (7 questions) — 22 questions in all, each solved step by step here.
Which method for the mean of grouped data is best?
All three give the same mean. The step-deviation method is quickest when the class marks are large and all classes have the same width.

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