Answer:
12%
Explanation:
First, converting R percent to r a decimal
r = R/100 = 12%/100 = 0.12 per year,
then, solving our equation
I = 3900 × 0.12 × 0.25 = 117
I = $ 117.00
The simple interest accumulated
on a principal of $ 3,900.00
at a rate of 12% per year
for 0.25 years is $ 117.00.