2 questions
In preparing a report on the economy, we need to estimate the percentage of businesses that plan to hire additional employees in the next 60 days.
a) How many randomly selected employers must we contact in order to create an estimate in which we are
9595%
confident with a margin of error of
99%?
b) Suppose we want to reduce the margin of error to
33%.
What sample size will suffice?
c) Why might it not be worth the effort to try to get an interval with a margin of error of
11%?
From a survey of coworkers you find that
4848%
of
150150
have already received this year’s flu vaccine. An approximate
9898%
confidence interval is
(0.3850.385,
0.5750.575).
a) How would the confidence interval change if the sample size had been
24002400
instead of
150150?
b) How would the confidence interval change if the confidence level had been
9595%
instead of
9898%?
c) How would the confidence interval change if the confidenc
