HW6_skeleton

7.2

• 1. Standard normal distribution
• 2. Area
• 3. 0.3085
• 4. 0.4207
• 1. 0.0071

  2. 0.3336

  3. 0.9115

  4. 0.9998

• 1. 0.9987

  2. 0.9441

  3. 0.0375

  4. 0.0009

• 15. 0.67
• 17. z1 = -2.575, z2 = 2.575
• 18. Z1 = -1.88, z2 = -1.88

shadenorm(mu=50, sig=7, above = 35,col = "blue",dens = 150)

• 24. type answer here.

shadenorm(mu=50, sig=7, above = 65,col = "blue",dens = 150)

• 25. type answer here.

shadenorm(mu=50, sig=7, below = 45,col = "blue",dens = 150)

• 1. 0.8658

  2. 0.0132

  3. 70.19%

  4. 12.30%

  5. 96th percentile

  6. 4th percentile

8.1

• 1. Sampling distribution
• 2. µ, σ/√n
• 3. Standard error, mean
• 4. True
• 5. False
• 6. False
• 7. Sampling distribution is normal, mean/center = 30, standard deviation/spread = 8/squareroot of 10
• 8. No because the shape of the underlying population does not matter.
• 9. µX(bar) = 80, σX(bar) = 2
• 10. µX(bar) = 64, σX(bar) = 3
• 1. Sampling distribution (shape), center = 80, spread is 14

  2. 7 samples will have a mean greater than 83

  3. 2 samples will have a mean less than or equal to 75.8

  4. 78 of the samples will have a mean inbetween 78.3 and 85.1

• 1. 35 of the pregnancies

  2. The sample distribution is normal withµX(bar) = 226, σX(bar) = 3.578

  3. 5 of the samples

  4. 4 of the samples

  5. Sample came from a population where the mean gestation period was less than 266 days

  6. 98 of the samples