Let f(x) = 11x + 2x^2 and g (x) = -7x - 3x^2 + 4 . Find (f + g) (x) and (f - g) (x) . Then evaluate f + g and f - g for x = 2

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.