Equitable Inc. finances its operations using debt and equity. The annual cost of equity is $15\mathrm{.}21$ percent and the annual after$-$tax cost of debt is $4\mathrm{.}38$ percent. The weight of the company's debt is $3/4$ and the weight of the company's equity is $1/4.$

Calculate Equitable Inc.$\text{'}$s weighted average cost of capital.

Group of answer choices

$12\mathrm{.}50$ percent

$7\mathrm{.}43$ percent

$7\mathrm{.}09$ percent