A company tht depends heavily on advertising for selling its products
wants to know if its various advertising media have different
effectiveness relative to the age of the customer.  the company uses
its warranty return cards to collect the following information:

type of advertisement     21-30   31-40   41-50   over 50  totals

store display               21      28      8       6        63
catalog                      8       5      1       1        15
magazine                     1      23      8       1        33
newspaper                   18      14      2       4        38

totals                      48      70     19      12       149

-Set up the hypotheses to test whether type of advertisement and age
of customer are independent.
-What population willthe test apply to?
-Calculate the expected frequencies for each cell
-How many degrees of freedom will the test have?
-At the 0.05 level of significance, are type of advertisement and age
of customer independent?
-What categories would you recommend collapsing to fix the problem?
-Without collapsing any cells, calculate the value of the ch-square
test statistic.

Well, usually I do not comment the content of questions.  But let me
give some advice : Try to find out what statistics are about by
reading schoolbooks describing the basic methods of statistical
mathematics.
Making homework can be boring - espacially when the subject seems
uninteresting. But later in your life you will very often see that it
can be rewarding to have studied things and found out solutions to
problems by yourself instead of paying others to do the homework for
you.
Please do not see this as criticsim - itīs meant to be a friendly
advice.

Maybe this can be helpful:
The Statistics Homepage
( http://www.statsoftinc.com/textbook/stathome.html )
or
UCLA Statistics Texbook
(Remark: watch the excellent printed formulas there !)
( http://ebook.stat.ucla.edu/textbook/ )

Search Strategy:
( ://www.google.de/search?sourceid=navclient&hl=de&querytime=y64xwB&q=statistics+textbook
)
There are a lot more etxtbooks available online.

till-ga