QUESTION

# Books Games amp;amp; Movies Total Under 20 ears old 120 200 20 years old or more 2 40 300 320 180

Bingo's bookstore wants to determine how much of its floor space to use for books, and how much for games and movies. 500 customers are asked if they visit the store primarily for books, or primarily for games and movies. The customers are also divided by age group. The results of this survey are shown in the contingency table below:

One customer is selected at random. Find the following probabilities. Express your answers as percentage.

a.   The person is under 20 years old and primarily visits the store for books.

b.   The person is under 20 years old or primarily visits the store for games and movies.

c.   The person visits the store primarily for books, given that he is 20 years old or more.

d.   The person is 20 years old or more, given that he visits the store primarily for books.

e.   Are age & primary merchandise statistically independent events?

2.A small rental franchise keeps detailed records of vehicles being returned damaged. In one year, 360 out of 3000 trucks and 120 out of 1000 automobiles were returned damaged. In all, 480 of a total of 4000 vehicles were returned damaged. Are type of vehicle and damaged/undamaged statistically independent events?

3.In a survey of 800 adults over the age of 50, 640 said they would consider coloring grey hair, while 240 said they would consider plastic surgery for wrinkles. 160 adults said they would consider both hair coloring and plastic surgery. Are considering hair coloring and considering plastic surgery statistically independent events?

4.If one of the adults in problem #3 is randomly selected, what is the probability that he/she will not consider plastic surgery?

1. For each of the following, state whether the events created are mutually exclusive and whether they are collectively exhaustive.