A company with three different product lines, X, Y and Z, selling for £6, £5 and £4 each respectively, incurs a £9,000 advertising cost to get the company’s name publicised.

Unit sales of the products are in the proportions X 25%, Y 35% and Z 40%, and annual turnover is £242,500, split X £75,000, Y £87,500 and Z £80,000. Which of the following ratios would be a reasonable basis for reapportionment of the advertising cost?

(a) 6:5:4

(b) 25:35:40

(c) 75:87.5:80