We have not included the solutions to the following examples in the summary pages.

Question

Consider a raffle of 100 tickets in which Anne Brown bought seven tickets. Tony Ng also bought four of these 100 tickets. What is the probability that either Anne or Tony win?

(Solved in full version)

The next example is based on a real data set.

Question

The following contingency table describes all 121,690 couples who were married in Australia in 2011.

Previous marital status of couple Both partners
born in Australia
Both partners
born in same
overseas country
Born partners in
different countries
First marriage both partners 51,663 10,522 24,630
First marriage one partner 9,450 2,910 8,050
Remarriage both partners 6,769 1,889 5,807

In a randomly selected marriage from 2011, what is the probability that either it was the first marriage of both partners or that both partners were born in Australia?

(Solved in full version)