Some boxes of a certain brand of breakfast cereal
include a voucher for two free movie tickets
inside the box. The cereal company claims that a
voucher can be found in 25 percent of the boxes.
However, based on their experiences eating this
cereal at home, a group of students believes that
the proportion of boxes with vouchers is less than
0. 25. This group of students purchased 65 boxes
of the cereal to investigate the company's claim.
The students found a total of 11 vouchers for two
free movie tickets in the 65 boxes. Assume that
the 65 boxes purchased by the students are a
random sample of all boxes of this cereal.
Based on this sample, is there support for the
students' belief that the proportion of boxes with
vouchers is less than 0. 25? Answer by performing
all steps of a hypothesis test with a = 0. 5.