Overview: The company, EDF, is one of the largest energy suppliers in Europe with 5M customers. In this clip customers want telephone operator Will, to give them a price comparison with their existing company. He uses of a formula where a higher rate is charged on the first 5480kw of energy and the remainder is charged at a lower rate. Once the total has been calculated Will needs to add the VAT percentage. The customer could make a saving of over £50 by changing to EDF. During the call he uses a formula, percentages, decimals, proportions and a calculator.