At a certain company, the sales records of 30 employees were examined. Fifteen of the employees were married and 15 of them were not married. The following statistical information was calculated from the number of sales of each employee chosen.

Married Unmarried
Mean 113 97
Median 103 105
Mode 94 105
Range 80 84

According to a study conducted in 2015, 18% of shoppers said that they prefer to buy generic instead of name-brand products. suppose that in a recent sample of 1500 shoppers, 315 stated that they prefer to buy generic instead of name-brand products. at a 5% significance level, can you conclude that the proportion of all shoppers who currently prefer to buy generic instead of name-brand products is higher than .18? use both the p-value and the critical-value approaches.