MA145 Final Exam - Takehome Portion
For each of the problems below, use the MA145 technology guide to perform a statistical analysis.
You should justify your choice of method, including any assumptions made in the use of the method.
You should indicate whether a two-tailed, left-tailed, or right-tailed analysis is appropriate,
and, in hypothesis testing problems, state the null and alternative hypotheses.
If the problem does not specify a level of significance, you should choose one.
Problem 1
A researcher counts the eggs in 52 Eastern bluebird (Sialia sialis) nests and
finds an average of 2.7. A large survey from previous years had a mean of 3.0 eggs
and a standard deviation of 0.6. Does this years sample indicate a significant decline
in the number of eggs per nest compared to last year?
Problem 2
A random sample of 62 people is given a questionairre that asks if they have a favorable,
neutral, or unfavorable attitude towards Muslims. If 18 respond that they have an
unfavorable opinion, what is the 95% confidence interval for the proportion of the population
that has an unfavorable attitude towards Muslims?
Problem 3
A gardener wants to test the effect of a fertilizer. The gardener treats 47 tomato
plants with the fertilizer, and leaves 35 plants untreated. At the end of the season,
the average weight of tomatos from the treated vines is 3.2 pounds with a standard
deviation of 1.8. The average weight from the untreated vines is 2.9 pounds with a
standard deviation of 2.0. Does this data support the claim that the fertilizer increases
the yield per plant?