CBSE · Class 8 · Mathematics · Chapter 12

Tales by Dots and Lines

Use dots, lines, graphs and networks to recognise patterns and solve connected mathematical problems.

13 lessons 50 min
Start chapter

Lessons in this chapter

  1. 1The Mean as a Balance PointUnderstand the mean through fair sharing, dot plots, and balanced distances.
  2. 2How Adding or Removing Data Changes the MeanPredict and explain changes to a mean when observations enter or leave a dataset.
  3. 3Shifting and Scaling DataExplain how the mean changes when every observation is adjusted in the same way.
  4. 4The Median When Data ChangesTrack middle positions when data is inserted, removed, or repeated.
  5. 5Working Backwards from a MeanRecover totals, find missing observations, correct errors, and construct datasets.
  6. 6Mean and Median from Frequencies and Dot PlotsUse repeated observations efficiently and interpret the information a display actually contains.
  7. 7Exploring Data in a SpreadsheetOrganise a table, write formulas, and check what automated calculations mean.
  8. 8Reading and Drawing Line GraphsRead axes and legends, describe change over time, and construct a two-series line graph.
  9. 9Comparing Trends and Testing ClaimsInterpret multiple lines, rainfall seasons, and claims about missing information.
  10. 10Moving Between Tables and GraphsPlot rainfall and price data, recover approximate values, and choose appropriate totals and comparisons.
  11. 11Infographics and Time-Use StripsDecode a comparison index and represent a complete day with half-hour cells.
  12. 12Data Stories Across TimeInterpret sleep and household data, compare clock times, and design a small investigation.
  13. 13Chapter Summary and PracticeConnect the chapter’s ideas through mixed problems and finish with Game of Hex.
← All Class 8 Mathematics chapters