Question 1190286
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Rajesh is loaned $28,250 and must pay this amount back, plus interest. 


There are roughly 52 weeks in a year
Over the course of 8 years, that will be 52*8 = 416 weeks total.
That means Rajesh has n = 416 car payments to make.


The annual interest rate is r = 2.79% = 0.0279
The weekly interest rate is r/52 = 0.0279/52
I'll leave it as a fraction like that.


The formula to calculate his payments is
{{{P = (L*i(1+i)^n)/((1+i)^n-1)}}}
L = loan amount = 28,250
i = interest rate per period = 0.0279/52
n = number of periods = 416


Crunching the numbers gets the following
{{{P = (L*i(1+i)^n)/((1+i)^n-1)}}}


{{{P = (28250*(0.0279/52)(1+0.0279/52)^416)/((1+0.0279/52)^416-1)}}}


{{{P = 75.7870907}}} approximately


{{{P = 75.79}}}


Rajesh will have a weekly car payment of <font color=red>$75.79</font>


If that amount is paid per week for 416 weeks, then 416*75.79 = <font color=red>$31,528.64</font> is paid back overall. 


The difference of that figure and the amount loaned is the total interest 
31,528.64 - 28,250 = <font color=red>$3,278.64</font>


Extra info: 
The effective interest rate is roughly 11.61% interest because (3278.64)/(28250) = 0.1161 = 11.61% which is much higher than the 2.79% stated APR. 
The reason why the large jump is because Rajesh decided to go for the max length of the loan repayment. The longer the loan is in existence, the more interest there is to be made from it (hence the higher effective interest rate).
The trade off however is that he has lower weekly payments.


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Answers:
Weekly payment is <font color=red>$75.79</font>
How much is paid off in total? <font color=red>$31,528.64</font> (principal + interest)
How much interest will be paid? <font color=red>$3,278.64</font>
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