(variance 16). Find .

Answer and explanation

Correct answer: D. 0.0228

  1. Step 1: The standard deviation is . Step 2. . Step 3. . Answer: 0.0228. Why not the others: 0.0456 doubles it for two tails; 0.9772 is ; 0.3085 uses 16 as the standard deviation, giving .

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