HW6_skeleton

7.2

• 1. Standard normal distribution
• 2. Za is a
• 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. z = 0.67
• 17. z = -2.575 z = 2.575
• 18. z = -2.75 z = 2.75
• 23. P(X>35) = 0.9838

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

• 24. P(X>65) = 0.0162

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

• 25. P(X</= 45) = 0.2389

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

• 1. P(1000<X<1400) = 0.8658

  2. P(X<1000) = 0.0132

  3. P(X>1200) = 0.7019

  4. P(X<1125) = 0.1230

  5. 96th percentile

  6. 4th percentile

8.1

• 1. Sampling distribution
• 2. mew, sigma/mew
• 3. Standard error of the mean
• 4. False
• 5. False
• 6. True
• 7. M = 30, sigma = 2.530, shape is normal (Need the shape, center and spread)
• 8. No because the sample size is already big enough for it to be approximately normally distributed with M = 50 and sigma x-bar = 0.6325.
• 9. M = 80; sigma = 2
• 10. M = 64; sigma = 3
• 1. Sampling distripution is approximately normally shaped with M = 80 and sigma = 2 (Need the shape, center and spread)

  2. 0.0668

  3. 0.0179

  4. 0.7969

• 1. 0.3557

  2. M = 266; sigma x-bar = 3.578

  3. 0.0465

  4. 0.0040

  5. The population that the sample came from has a mean gestation period less than 260 days.

  6. 0.9844