Interest payments are tax deductible, therefore aftertax cost of debt would be:

Rdnt = Rate・(1-TaxRate) = 0.082・(1-0.35) = 0.0533 = 5.33%

and WACC would be: WACC = 0.6・0.135 + 0.05・0.065 + 0.35・0.082・(1-0.35) = 0.102905 ≈ 10.29%

Mullineaux Corporation has a target capital structure of 60 percent common stock, 5 percent preferred stock, and 35 percent debt. Its cost of equity is 13.5 percent, the cost of preferred stock is 6.5 percent, and the cost of debt is 8.2 percent. The relevant tax rate is 35 percent.

What is the aftertax cost of debt?