How common is online personal data theft? A survey of internet users found that 15% of the 18 to 29 year olds, 20% of the 30 to 49 year olds, 20% of the 50 to 64 year olds, and 13% of the 65+ year olds have had important personal information stolen. (Data extracted from How Common is Online Personal Data Theft? available at bit.ly/1rKlqRW.) Suppose the survey was based on 200 Internet users in each of the four age groups: 18–29, 30–49, 50–64, and 65+. 

a. At the 0.05 level of significance, is there evidence of a difference among the age groups in the proportion of internet users who have had important personal information stolen? 

b. Determine the p value in (a) and interpret its meaning.