Joe deposited $2500 into a savings account earning 4% compounded monthly. If he makes no other deposits or withdrawal, how much will he have in the account in three years?

Answer:
2500=100
**. =4
2500×4/100=100
100×12 because 1 year have 12 months
then 3×1200=3600
[tex]~~~~~~ \textit{Compound Interest Earned Amount}[/tex]
[tex]A=P\left(1+\frac{r}{n}\right)^{nt} \quad \begin{cases} A=\textit{accumulated amount}\\ P=\textit{original amount deposited}\dotfill &\$2500\\ r=rate\to 4\%\to \frac{4}{100}\dotfill &0.04\\ n= \begin{array}{llll} \textit{times it compounds per year}\\ \textit{monthly, thus twelve} \end{array}\dotfill &12\\ t=years\dotfill &3 \end{cases} \\\\\\ A=2500\left(1+\frac{0.04}{12}\right)^{12\cdot 3}\implies A=2500\left( \frac{301}{300} \right)^{36}\implies A\approx 2818.18[/tex]