An analyst at a local bank wonders if the age distribution of customers coming for service at his branch in town is the same as at a branch located near the mall.He selects 100 transactions at random from each branch and researches the age information for the associated customer.These are the data :

Age

Less than 30 30-55 56 or older Total

in town 20 40 140 100

mall 30 50 20 100

Total 50 90 60 200

things to think about:

1)What is the null hypothesis if you want to check if the age patterns of customers are independent of bank location?

2)What are the expected numbers for each cell in a 3 by 3 table if the null hypothesis is true?

3)Use the chi square test to accept or reject the null hypothesis.What is the chi square test statistic?

4)What is the chi square critical value and how many degrees of freedom does it have?Assume alpha is .05.

5)What do you conclude?