Paper 2 · Statistics ⏱ Tested in 5 exam questions since 2018 Lesson 9 of 21

Statistics 9 – z-scores 1

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You’ll learn

  • Interpret a z-score as a number of standard deviations above or below the mean
  • Read P(z ≤ a) for positive a from the standard normal tables on pages 36/37
  • Use symmetry to state P(z ≤ 0) = 0.5 without a table lookup

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