Paper 2 · Statistics ⏱ Tested in 2 exam questions since 2016 Lesson 18 of 21

Statistics 18 Central Limit Theorem, trends in population proportion

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You’ll learn

  • State the Central Limit Theorem: 30+ sample means always form a normal curve
  • Explain why population size doesn't matter for inference — only sample size n
  • Show p(1−p) peaks at p = 0.5, making 1/√n the worst-case margin of error
  • Explain why halving the margin of error needs four times the sample size

Most recent exam questions

  • 2018 P2 Q8(b)(ii)
  • 2016 P2 Q9(c)

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