According to BIG research holiday shoppers spent an average

According to BIG research, holiday shoppers spent an average of $373 over the Thanksgiving weekend in 2008. In 2009 a random sample of 16 shoppers found an average of $326 and a standard deviation of $103 for the same weekend. This caused retailers to be concerned that the recent economic downturn was going to affect the upcoming holiday sales. With your knowledge of statistics would you say that this theory is significant-----------My question is why this is not left tail test?( because 326 is less than 373)

Solution

that is because as you can see the sentences

According to BIG research, holiday shoppers spent an average of $373 over the Thanksgiving weekend in 2008

so we are doing a hypothesis test to see if the BIG reasearch is true that the mean is 373

if there is not then can be greater or lower tha that value

$326 is only for your random sample

not is for the hypothesis