E
Amount spent: X= $38.54, S = $7.26.
Eighteen customers purchased dessert.
a. Construct a 95% confidence interval estimate for the population
mean amount spent per customer in the restaurant.
b. Construct a 90% confidence interval estimate for the population
proportion of customers who purchase dessert.
Jeanine, the owner of a competing restaurant, wants to conduct a
similar survey in her restaurant. Jeanine does not have access to the
information that Scarlett and Heather have obtained from the survey
they conducted. Answer the following questions:
c. What sample size is needed to have 95% confidence of estimat-
ing the population mean amount spent in her restaurant to within
$1.50, assuming that the standard deviation is estimated to
be $8?
d. How many customers need to be selected to have 90% confi-
dence of estimating the population proportion of customers who
purchase dessert to within ±0.04?
e. Based on your answers to (c) and (d), how large a sample should
Jeanine take?
- does anyone know this problem? Please help