One of the stations Tom gets in his random sample is Manchester Piccadilly. To find opinions, he goes there one Saturday afternoon and asks his questions to the first 100 people who will answer. Name this sampling method.

**Opportunity sampling** (also known as convenience sampling) is a type of non-probability sampling that involves the sample being drawn from that part of the population that is close to hand. Tom is not using a random or systematic method to select individuals; he is simply approaching people who are present at Manchester Piccadilly on a Saturday afternoon and are willing to answer. It is convenient for him but is not random and is likely to be biased.