Problem 17

  1. 15.6 %, +- 3.0 %

  2. I’m 95% confident that our model contains the true value of teenage drivers in accidents in the range of 15.6% +- 3%

  3. 95% of all samples with this confidence interval using 2 standard deviations will contain the true value

  4. not true, contradictary since the interval is less than 20%

Problem 23

  1. (18.2%, 21.8%)

  2. Interval 18%-22%, 98% confident that the true proportion fo defient childred in vitimin D exsists between the interval

  3. We can conclude this becuase 98% of all sample with these deviations will contain the true proportion

Problem 29

  1. 141

  2. 318

  3. 564

Problem 31

  1. 1801 students would allow us to keep our confidence level at 95%