Question

Answer:5. Selina Kyle borrowed $3,000 from a bank for 8 months at a simple interest rate of 5.0%a. How much interest was charged?Answer:b. How much did she have to pay back to the bank? Answer:

Answer 1

Solution:

The simple interest charged on an amount borrowed at a given rate for a given period of time is expressed as

$\begin{gathered} I=P\times R\times T \\ where \\ P\Rightarrow amount\text{ borroewd} \\ R\Rightarrow interest\text{ rate, expressed in percentage } \\ T\Rightarrow time\text{ in years} \end{gathered}$

A) Interest charged:

Given that

$\begin{gathered} P=3000 \\ R=5\%=\frac{5}{100} \\ T=8\text{ months=}\frac{8}{12}\text{ year} \end{gathered}$

Thus, the interest charged is evaluated as

$\begin{gathered} I=3000\times\frac{5}{100}\times\frac{8}{12} \\ =\ 100 \end{gathered}$

Hence, the interest charged is $100.

B) Amount to be paid back:

The amount to She will pay back is the sum of the amount borrowed and the interest charged.

Thus,

$\begin{gathered} Amount\text{ =Principal + Interest charged} \\ =3000+100 \\ \Rightarrow Amount\text{ to be paid = \ 3100} \end{gathered}$

Hence, the amount she will pay back is

$\ 3100$