HW6_skeleton

7.2

• 1. standard normal distribution
• 2. 1
• 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
• 23. P(X>35)=0.9838

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

• 24. P(X>65)=0.016

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. 0.7019 of the bags have more than 1200 chocolate chips

  4. 0.1230 of the bags have fewer than 1125 chocolate chips

  5. a bag that contains 1475 chocolate chips is at the 96th percentile

  6. a bag that contains 1050 chocolate chips is at the 4th percentile

8.1

• 1. sampling distribution
• 2. u, o/sq root of n
• 3. standard error, mean
• 4. standard, error, mean
• 5. false
• 6. false
• 7. ux=30 and ox=8/square root of 10 = 2.530.
• 8. ux=50 and ox=4/sq root of 40 = 0.6324
• 9. ux=80, ox=2
• 10. ux=64, ox=2
• 1. x is approximately normal with ux = 80, ox = 2

  2. P(x>83)=0.0668

  3. P(x<75.8)

  4. P(78.3<x<85.1)=0.7969

• 1. 0.3520

  2. normal ux=266 and ox=16/sq root of 20 = 3.578

  3. 0.0465

  4. 0.004

  5. not normal result - sample came from a population with mean gestation period less than 266 days

  6. 0.3085