Calculate the interest coverage ratio (earnings based) before tax, if sales are 1000, cost of sales are 600, operating earnings are 100, earnings after the financial net is 80, the profit after tax is 60, inventory is 200, trade receivables are 150, trade payables are 250, business assets are 800 and equity 400. The tax rate is 25 per cent and the depreciations are 10. The total debt in the company is 150.