Question: Calculate the mean and standard deviation if you have not already done so. Given that this data is a sample, calculate the 90 per cent, 95 per cent and 99 per cent confidence intervals around the mean. Provide a management interpretation of these in the context of the problem and explain why the interval gets larger.

Exercise: The leisure services committee of a local authority has seen its budget decline over the last few years and is currently having to consider closing a number of its leisure facilities - sports halls, small parks, museums and so on. One closure being considered is that of a small branch library in an outlying village. As a preliminary aspect of the decision some data has been collected on the number of people using the library and its facilities:

Calculate suitable measures of average and dispersion for this data.