Answer:
The annual rate of return is 13.14%.
Explanation:
As it is not mentioned whether the amount was compounded, so we will assume this to be simple interest.
Given is - A $3500 loan was settled ten years later with a payment of $8100.
Means total amount paid back was = $8100
And original principle was = $3500
So, interest paid =
dollars
Now simple interest formula is :

Where p = 3500
I = 4600
r = ?
t = 10
Now putting these values in formula we get;


r= 0.1314
So, rate of interest = 13.14%