Lesson 3p.13

3p.13 Know that, for a normal distribution, values more than three standard deviations from... Quiz: Pearson Edexcel Statistics, Unit 3

20 questions

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Lesson 3p.13, Know that, for a normal distribution, values more than three standard deviations from...: 20 multiple choice questions for the Pearson Edexcel GCSE Statistics (1ST0), Unit 3: Probability, written with Revision Ninja.

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The 20 questions

  1. In a normal distribution, what percentage lies within 1 standard deviation of the mean?

    • About 50%
    • About 99.7%
    • About 68%
    • About 95%

  2. About what percentage of a normal distribution lies within 2 standard deviations of the mean?

    • About 95%
    • About 68%
    • About 50%
    • About 99%

  3. In a normal distribution, values beyond three standard deviations are termed what?

    • Very common
    • Very unusual
    • Expected values
    • Standard values

  4. Roughly what percentage of a normal distribution lies beyond 2 standard deviations on both sides combined?

    • About 50%
    • About 2%
    • About 5%
    • About 32%

  5. What percentage of data lies within one standard deviation of the mean?

    • 99%
    • 50%
    • 68%
    • 95%

  6. What shape must a distribution have to be a normal model?

    • Triangular
    • Bell shape
    • Rectangular
    • Exponential

  7. For a normal distribution with mean 50 and SD 5, which value is most unusual?

    • 55
    • 52
    • 66
    • 48

  8. A value lies 1 SD below the mean in a normal distribution. About what percentage of data lies below it?

    • About 50%
    • About 84%
    • About 34%
    • About 16%

  9. Heights are normal with mean 160 cm and SD 8 cm. Between which values do about 95% lie?

    • 136 cm and 184 cm
    • 160 cm and 168 cm
    • 152 cm and 168 cm
    • 144 cm and 176 cm

  10. Test marks are normal with mean 70 and SD 6. Between which values do about 68% lie?

    • 70 and 76
    • 58 and 82
    • 67 and 73
    • 64 and 76

  11. Weights are normal with mean 500 g and SD 10 g. About what percentage lie between 480 g and 520 g?

    • 68%
    • 99.7%
    • 50%
    • 95%

  12. Lengths are normal with mean 25 cm and SD 2 cm. About what percentage are above 29 cm?

    • 16%
    • 2.5%
    • 5%
    • 34%

  13. Values are normal with mean 40 and SD 4. Which value is more than 3 SD from the mean?

    • 50
    • 47
    • 53
    • 44

  14. Normal with mean 10 and SD 2. About what percentage lie between 8 and 12?

    • 68%
    • 50%
    • 95%
    • 34%

  15. Battery lives have a mean of 7 hours and a 95% range of 4 to 10 hours. What is the standard deviation?

    • 3 hours
    • 1 hour
    • 1.5 hours
    • 2 hours

  16. Roughly what percentage of a normal model lies outside 2 standard deviations?

    • 1%
    • 32%
    • 5%
    • 68%

  17. Why does a data point at four standard deviations suggest a non-normal distribution?

    • Guaranteed
    • Extremely rare
    • Impossible
    • Very common

  18. If only 40% of data lies within one SD instead of 68%, what does this suggest?

    • Perfect fit
    • Normal model
    • Uniform model
    • Not normal

  19. What do values beyond three standard deviations help identify in a dataset?

    • Modes
    • Quartiles
    • Outliers
    • Medians

  20. In 1000 normal values with mean 0 and SD 1, about how many are above 3?

    • About 100
    • About 50
    • About 10
    • About 1

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