2 Jenny has to do a statistics project at school on how much pocket money, in dollars, is received by students in her year group. She plans to take a sample of 7 students from her year group, which contains 122 students.
- Give a suitable method of taking this sample.
Her sample gives the following results.
$$\begin{array} { l l l l l l l }
13.40 & 10.60 & 26.50 & 20.00 & 14.50 & 15.00 & 16.50
\end{array}$$
- Find unbiased estimates of the population mean and variance.
- Is the estimated population variance more than, less than or the same as the sample variance?
- Describe what you understand by 'population' in this question.