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Explanation:
The down payment and trade-in value add to 4000+6500 = 10,500
Subtract this total from the car's cost
42,100 - 10,500 = 31,600
This is the amount loaned to the customer.
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We have these input values
Let's compute the monthly payment
P = (L*i)/(1 - (1+i)^(-n))
P = (31600*0.00375)/(1 - (1+0.00375)^(-60))
P = 589.119408031938 approximately
P = 589.12