clickers: normal distributions

Suppose Z ~ N(0, 1). Use the standard Normal table or your calculator to find P(z  -2.30). 10

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0.0107 0.0099 0.9893 0.9901 0.9898

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Suppose Z ~ N(0, 1). Use the standard normal table or your calculator to determine P(-2.25 < z < 1.77). 10

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0.9494 0.9415 0.9477 0.9616 0.9432

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What is the 50th percentile of the standard normal distribution? 10

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z = 0.50 z = 0.0 z = -0.5 z = 1.0 z = -1.0

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What is the 67th percentile of the standard normal distribution? 10

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z = 0.67 z = 1.67 z = 0.44 z = -0.44 z = -0.67

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The SAT scores of incoming NCSU freshmen can be approximated by a normal model with mean 1775 and standard deviation 135 (2400 point scale). What proportion of incoming freshmen score between 2072?20% 20% 20% 1559 20%and20% 10

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0.0409 0.9313 0.6 0.9320 .513 1.

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The SAT scores of incoming NCSU freshmen can be approximated by a normal model with mean 1775 and standard deviation 135 (2400 point scale). The scholarship office will offer scholarships to students who score in the top 25% 25% 25% 25% 2.28%. What is the lowest score a student can achieve and be eligible for a scholarship? 10

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1505 2045 1908.47 1641.53 1

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A box of Extreme Choco Loops cereal is marked “Net Wt. 12 oz.” If the actual weight can be approximated by a normal model with mean 12 oz. and standard deviation 0.2 oz, what is the probability 20% 20% that 20% a box 20% 20% weighs less than 12 oz? 10

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0.68 0.12 0.50 0.34 0.84 1.

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A box of Extreme Choco Loops cereal is marked “Net Wt. 12 oz.” If the actual weight can be approximated by a normal model with mean 12 oz. and standard deviation 0.2 oz, what weight will exceeded by 2.5% 20% be20% 20% 20% 20% of the boxes? 10

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12.392 oz. 11.608 9.50 oz. 12.199 oz. 11.80 oz. 1

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The cholesterol levels of adult American women can be approximated by a normal model with mean 188 mg/dL and a standard deviation of 24. Approximately what cholesterol value is the cutoff for20%the first quartile 20% 20% 20% 20% of adult American women cholesterol levels? 1. 2. 3. 4. 5.

164.15 171.8 204.19 182 194

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