Answer:
66.67%
Step-by-step explanation:
First, we need to calculate the Interest paid
Tax Paid = 25% x 8% = 2%
Tax paid is the nominal rate, now we need to calculate the real rate.
Before-tax real interest rate = Nominal Interest rate - Inflation rate
Before-tax real interest rate = 8% - 5% = 3%
True Income Tax rate = Tax paid / Before-tax real interest rate
True Income Tax rate = 2% / 3%
True Income Tax rate = 66.67%