Problem 31

36.33 inches should be theorhetical mean for all trails

thoerhetical standard deviation should be

a1) 2.842 b1) 1.797 c1) 1.271 d1) 0.899

  1. Pretty close

  2. I’d be comfortable using anything larger than 5

  3. Unimodal, symettric, relatively unskewed

Problem 37

N(266, 16)

p=21% of pregnacys

  1. 276.79 days

  2. 60 women sample

N(mean, sd/sqrt(n))

N(266, 2.07)

  1. 0.0018

1.8%

Problem 39

  1. It is statisiticlly more likely to have a baby earlier rather than later. More abortions/early briths than prolonged births

part a) change part b) change part c) wouldn’t change

problem 41

  1. expected value = 2 sd = 3.61

  2. expected value = 4 sd = 5.105

  3. (80, 22.83) 19%