Consider this case:

Globex Corp. is an all-equity firm, and it has a beta of 1. It is considering changing its capital structure to 70% equity and 30% debt. The firms cost of debt will be 6%, and it will face a tax rate of 25%.

What will Globex Corp.s beta be if it decides to make this change in its capital structure?

1.58

1.72

1.32

1.52

Now consider the case of another company:

US Robotics Inc. has a current capital structure of 30% debt and 70% equity. Its current before-tax cost of debt is 6%, and its tax rate is 25%. It currently has a levered beta of 1.15. The risk-free rate is 2.5%, and the risk premium on the market is 7.5%. US Robotics Inc. is considering changing its capital structure to 60% debt and 40% equity. Increasing the firms level of debt will cause its before-tax cost of debt to increase to 8%.

First, solve for US Robotics Inc.s unlevered beta.

0.78

0.96

0.87

1.04

Use US Robotics Inc.s unlevered beta to solve for the firms levered beta with the new capital structure.

1.85

1.76

2.04

1.67

Use US Robotics Inc.s levered beta under the new capital structure, to solve for its cost of equity under the new capital structure.

14.742%

13.104%

16.380%

18.837%

What will the firms weighted average cost of capital (WACC) be if it makes this change in its capital structure?

10.20%

9.69%

8.67%

8.16%