Suppose a mortgage has an interest rate of 6.5% per annum with monthly compounding. Find the per annum interest rate with quarterly compounding that would lead to the same effective annual rate.
I solved this one by:
$$r_eff = (1+\frac{0.065}{12}^{12})-1 =0.067%$$ $$(1+\frac{r}{4})^4-1=0.067$$ $$=(1+\frac{r}{4})= (1+0.067)^{\frac{1}{4}}$$
Solving for r, I get 6.52%
Now how would I find the rate with continuous compounding that would lead to the same effective annual rate? I understand that the formula is $$A=Pe^{rt}$$ How would I set up the problem?