annas bank gives her a loan with a stated interest rate of 10.22%. how much greater will annas effective…

annas bank gives her a loan with a stated interest rate of 10.22%. how much greater will annas effective interest rate be if the interest is compounded daily, rather than compounded monthly? a. 0.5389 percentage points b. 0.1373 percentage points c. 0.4926 percentage points d. 0.0463 percentage points
Answer
Explanation:
Step1: Recall the effective - interest rate formula
The formula for the effective - interest rate $r_{eff}$ is $r_{eff}=(1 + \frac{r}{n})^{n}-1$, where $r$ is the stated annual interest rate and $n$ is the number of compounding periods per year. The stated interest rate $r = 0.1022$.
Step2: Calculate the effective - interest rate for monthly compounding
For monthly compounding, $n = 12$. Then $r_{eff1}=(1+\frac{0.1022}{12})^{12}-1$. [ \begin{align*} r_{eff1}&=(1 + 0.0085167)^{12}-1\ &\approx1.10717 - 1\ &=0.10717 \end{align*} ]
Step3: Calculate the effective - interest rate for daily compounding
For daily compounding, assume 365 days in a year, so $n = 365$. Then $r_{eff2}=(1+\frac{0.1022}{365})^{365}-1$. [ \begin{align*} r_{eff2}&=(1+\frac{0.1022}{365})^{365}-1\ &=(1 + 0.00028)^{365}-1\ &\approx1.107633-1\ &=0.107633 \end{align*} ]
Step4: Find the difference
The difference $\Delta r=r_{eff2}-r_{eff1}=0.107633 - 0.10717=0.000463$, which is $0.0463$ percentage points.
Answer:
d. 0.0463 percentage points