2 A market researcher wants to interview people who watched a particular television programme. Audience research data used by the broadcaster indicates that \(12 \%\) of the adult population watched this programme. This figure is used to model the situation.
The researcher asks people in a shopping centre, one at a time, if they watched the programme. You should assume that these people form a random sample of the adult population.
- Find the probability that the fifth person the researcher asks is the first to have watched the programme.
- Find the probability that the researcher has to ask at least 10 people in order to find one who watched the programme.
- Find the probability that the twentieth person the researcher asks is the third to have watched the programme.
- Find how many people the researcher would have to ask to ensure that there is a probability of at least 0.95 that at least one of them watched the programme.