The managers of a food company are interested in determining the effect on their sales of a competitor"s television advertisements.
An analysis of sales records for the last 120 weeks gives the following results:
|
|
Level of sales
|
|
(no. of weeks)
|
|
Low
|
Medium
|
High
|
Total
|
|
Competitor advertised
|
$32
|
$14
|
$18
|
64
|
|
Competitor did not
|
21
|
$12
|
$23
|
56
|
|
advertise
|
|
|
|
|
|
Total
|
53
|
26
|
41
|
120
|
Assuming that these past data are a reliable guide to the future, determine the probability that next week:
(a) The competitor will advertise;
(b) Sales will not be high;
(c) Medium or high sales will be achieved;
(d) Either the competitor will advertise or only low sales will be achieved;
(e) Either the competitor will not advertise or high sales will be achieved.