The maturity value of a loan is the total amount you must repay, including the principal and any interest you incur.
The interest is calculated by:
I = Prt
Where P is the amount of the loan, r is the interest rate and t is the time of the loan.
We are given:
P = $3345
r = 10.5%
t = 87 days
Convert the interest rate to daily by dividing by 365 (assuming a calendar 365-day year):

Calculate the interest (we keep all the decimals in the calculator):
I = $3345 x 0.00028767 x 87
I = $83.72
The maturity value (final value) of the loan is:
FV = P + I = $3345 + $83.72
FV = $3428.72