Taxed amount/tax rate = income

Tax amount/income = tax rate

By the way, there is also a question of interest.

Principal × interest rate× time = interest

Because there is interest tax, interest is divided into pre-tax interest and after-tax interest.

Pre-tax interest = principal × interest rate× time

After-tax interest = principal × interest rate × time ×( 1- interest tax rate) is generally 5%, that is, 1-5%.