The formula in computing the maturity value of the loan is:
MV = Principal + Interest
Interest = Principal (rate) (time in years)
Interest = 18,500 (4.5%) (180/360)
Take note that the 180 days is divided by 360 because time should be in years.
Interest = 18,500 (4.5%) (.5)
Interest = 416.25
MV = 18,500 + 416.25
Maturity value of the loan = 18,916.25