In a survey conducted on withdrawing money from automated teller machines, it is calculated that the mean amount of money withdrawn from the machines per customer transaction over the weekend is $160 with an expected population standard deviation of $30.
a. State the null and alternate hypotheses.
b. If a random sample of 36 customer transactions is examined and the sample mean withdrawal is $172, is there evidence to believe that the population average withdrawal is no longer $160 at a significance level of 0.05?
c. Compute the p-value and interpret its meaning.
d. What will be your answer in (b) if you use a 0.01 level of significance?
e. What will be your answer in (b) if the standard deviation is $24?