Answer:
Option D - 39.09%
Explanation:
Given : A credit card had an APR of 33.01% all of last year and compounded interest daily.
To find : What was the credit card's effective interest rate last year?
Solution :
Effective annual rate formula is given by,
where, r is the interest rate i.e. r=33.01%=0.3301
n is the number of time period for which interest is compounded daily i.e. n=365.
Substitute in the formula,
Into percentage,
![\text{APR}=39.089\%](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6biw2pufch8ap7julflfmnhay3clhexlhc.png)
![\text{APR}\approx 39.09\%](https://img.qammunity.org/2020/formulas/mathematics/middle-school/1lesfbab2j47mtgeqt2zd4ks251pa4cpbm.png)
Therefore, the credit card's effective interest rate last year is 39.09%.
So, Option D is correct.