The simple interest rate is 8%.
Calculation of the simple interest rate;
Since the borrowed amount is $750
The number of months is 9
And, the simple interest is $45
We know that
SImple interest = Principal * rate of interest * time period
$45 = $750 * rate of interest * 9/12
$45 = $750 * rate of interest * 0.75
So, the rate of interest is 8%
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