Question

Myra borrowed $1,500 at 12.5% interest for three months. How much

does she have to repay under a single-payment plan?
a. $46.88
b. $1,562.50
c. $1,546.88
d. $187.50

**please explain how you got the answer, it's just so that I can understand

Answer 1

now, this is for 3 months, and we're assuming, I guess it doesn't really matter, but using simple interest.

now, 3 months is not even a year, there are 12 months in 1 year, so 3 months is 3/12 years, or 1/4.


`\bf \qquad \textit{Simple Interest Earned}\\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\\ P=\textit{original amount deposited}\to& \$1500\\ r=rate\to 12.5\%\to (12.5)/(100)\to &0.125\\ t=years\to (3)/(12)\to &(1)/(4) \end{cases} \\\\\\ I=1500\cdot 0.125\cdot \cfrac{1}{4}\implies 46.875\approx 46.88`