AQ3.4: Activity Question 4

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Activity focus

• range calculation
• comparing spread
• variance vs standard deviation concepts

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Practice set

1. Find the range of 4, 9, 11, 15, 19.
2. Which dataset has zero spread?
   • 7, 7, 7, 7
   • 6, 7, 8, 9
3. Which statement is correct?
   • variance and standard deviation are identical
   • standard deviation is the square root of variance
   • range uses all values equally

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Answer key

1. 19 - 4 = 15
2. 7, 7, 7, 7
3. standard deviation is the square root of variance

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MCQ traps

• range depends only on min and max
• zero spread means all observations are the same