Answer:
A tax rate of 10.71% should make both both indifferent for investors.
Explanation:
the municipal bonds are income-tax free so we should solve for the tax rate which makes both bonds equaly attractive.
0.075 = after-tax rate
0.084 = pre-tax rate
[tex]pre-tax (1- t) = after-tax\\0.084 (1-t) = 0.075\\1 - t = 0.075 \div 0.084\\t = 1 - 0.075 \div 0.084\\t = 0.10714285[/tex]
A tax rate of 10.71% should make both both indifferent for investors.