In a recent survey, 10 percent of the participants rated Pepsi as being "concerned with my health." PepsiCo's response included a new "Smart Spot" symbol on its products that meet certain nutrition criteria, to help consumers who seek more healthful eating options.
a. Suppose a follow-up survey showing that 22 of 200 persons now rate Pepsi as being "concerned with my health", calculate the z statistic. (Round your answer to 3 decimal places.)
b. At ? = 0.05, would a follow-up survey showing that 22 of 200 persons now rate Pepsi as being "concerned with my health" provide sufficient evidence that the percentage has increased?