a. Find the probability of getting exactly 4 sleepwalkers among 5 adults.
b. Find the probability of getting 4 or more sleepwalkers among 5 adults.
c. Which probability is relevant for determining whether 4 is a significantly high number of sleepwalkers among 5 adults: the result from part (a) or part (b)?
d. Is 4 a significantly high number of sleepwalkers among 5 adults? Why or why not?
Refer to the accompanying table, which describes the numbers of adults in groups of five who reported sleepwalking (based on data from "Prevalence and Comorbidity of Nocturnal Wandering In the U.S. Adult General Population," by Ohayon et al., Neurology, Vol. 78, No. 20).
x P(x)
0........................0.172
1........................0.363
2........................0.306
3........................0.129
4........................0.027
5........................0.002