Beached is a retail outlet situated in a very popular tourist town not far from Canberra. It is very popular during school holidays, with the peak tourist season being in December and January.

Sales consist of cash sales to retail customers $(70\%)$ and credit sales to tourist operators $(30\%).$ Credit sales are collected $20\%$ in the month of sale, $60\%$ in the month following the sale and $20\%$ in the second month following the sale.