Problem 27

H0: mean1=mean2 ha mean1<mean2

P value = 0.021

The bigger bowl made people eat more, as we reject the null and adopt the hypothesis that size does matter.

Problem 29

  1. Yes, the sample sizes were large and the new scores are several standard deviations below the previous mean, creating a low p value.

  2. No, both smaples were very large so we would expect to have accurate results for the most part.

Problem 31

H0: mean1=mean2 Ha mean1 =/= mean2

p value: 0.973

But if we remove outlier

p value: 0.283

We cannot reject the null with either P value, and conclude that the heats randomly assigned do not affect preformance.

Problem 33

H0: mean1=mean2 ha mean1<mean2

P value: 0.1%

WE reject the null that mean velocity of regular tees equals mean velocity of stinger tees, and instead adopt the conclusion that the stinger tees have a higher average velocity.

Problem 35

  1. We are 95% confident, (74.8 178.05) contains the true difference for men and women

doesn’t include zero! so there is a difference

The trials are indepdenent

Trails are not random, but are probably representative

Normal Porbbailty plot is a staight line, so nearly normal.

Problem 37

  1. H0:mR - mN = 0 HA:mR - mN < 0

P-value = 0.0945. We fail to reject H0. These data show no evidence of a difference in mean number of objects recalled.