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Lesson 0 of 14

4 min

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Six match scores. Six numbers. Each number you collect is a reading. You want just one number to describe the batting.

Figure 1 — one heap of readings, described three ways.

Connecting the Dots… — one number for many readings. It also covers graphs that show them.

What you will learn

  • One number for many — one figure describes a whole set.
  • The mean — share the total equally.
  • The median — the middle one, once the readings are in order.
  • Two in the middle — an even count needs a halfway rule.
  • The mode — the value that appears most often.
  • One strange value — it moves the mean much more than the median.
  • Which one to report — the question decides.
  • Dots on a line — a dot plot shows every reading.
  • How far apart — the range is the largest minus the smallest.
  • Two bars for every item — a double-bar graph compares two groups.

Every lesson has a small lab. Tap it and watch the answer change.