A savings account (Mango) offers 6% APY but has a nonwaivable $3 monthly fee.
This is my best shot determining what the account's after-fee APR is:
If you have a $5,000 balance, this means that the APY drops to 5.44%. To find this: You’d earn $308.39 given that the 6% APY compounds monthly, which I found using this calculator https://www.bankofinternet.com/calculators/apy-interest-calculator. Subtract the total yearly fees of $36 from the $308.39 to get $272.39. To find out what percent $272.39 is of $5,000, I simply divided $272.39 by $5,000 and got 0.0544. To convert that to a percent, I moved the decimal two places to the right.
I'm not sure I did the calculation correctly. The site Doctor of Credit states that Mango's after-fee APY is 5.28%, not 5.44%.