I assume there is a tax rate, the reason we multiple by (1-Tax Rate) for cost of debt is because there is a tax shield on interest expense because it is deductible from your income. For equity (preferred and common), you pay with after-tax dollars.
ok, the previous guys that commented failed to do justice to your need.
What you should observed is if you were asked to use the book value or the market value. In the case where no such info was given, you’ll have to calculate WACC based on the market value using the same WACC formula.
WACC = Wd*Kd(1-t) + We*Ke + Wp*Kp
Wd = Weightof debt
Kd(1-t) = After tax cost of dent
We and Wp are both the weight of equity and preferred stock, and so on.
Lols yours isnt exactly any better. And you use Mkt Val because that is the value of your investment and require a return based on what it is worth today… I guess you failed to do justice to their need as well…