Calculate the mean: 8, 11, 19, 17, 15

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.

Plzz ! need the answer asap! 7% of 980

If a seller prepaid the taxes of $4,400 and the closing is set for may 19, using the 12 month/30 day method what will the buyer owe the seller as prorated taxes?