Question

Jarod borrowed $500 from his parents. His parents are charging a simple interest rate of 3%.

How much interest will Jarod pay if he pays his parents back in 6 months?

Will give medal :)

Answer 1

How about this answer?

A = $ 507.50

Equation:
A = P(1 + rt)

Calculation:
First, converting R percent to r a decimal
r = R/100 = 3%/100 = 0.03 per year,
putting time into years for simplicity,
6 months ÷ 12 months/year = 0.5 years,
then, solving our equation

A = 500(1 + (0.03 × 0.5)) = 507.5
A = $ 507.50

The total amount accrued, principal plus interest,
from simple interest on a principal of $ 500.00
at a rate of 3% per year
for 0.5 years (6 months) is $ 507.50.

Found it here - http://www.calculatorsoup.com/calculators/financial/simple-interest-plus-principal-calculator.php