Presley is organizing the school book sale. each stall will have 40 books on the shelf and 2 boxes of books with b books inside. presley also has 200 books in inventory to refill the shelves as books sell. this situation can be written as the following expression: 40s + (2b)s + 200 how many books should presley have ready if she plans to open 8 stalls and have 12 books in each box? a) 520 b) 712 c) 820 d) 1,622

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.