Answer:Each installment will be of 60 and 16th will be the last payment.
Step-by-step explanation:
To find the monthly repayment by Oscar we first find the sequence.
For that first we put [tex] n=1 [/tex] in
[tex] F(n)=900-60(n-1)[/tex]
[tex] F(1)= 900-60(1-1) = 900 [/tex]
Now for [tex]n=2 [/tex]
[tex] F(2)=900-60(2-1)=840[/tex]
For [tex]n=3[/tex]
[tex] F(3)=900-60(3-1)=900-120=780[/tex]
So the sequenxe is 900,840,780......
As the amount is decreasing by 900-840=840-780=60
Therefore each installment will be equal to 60
For last payment amount will become 0
i.e.[tex]F(n) =0[/tex]
[tex] 900-60(n-1)=0[/tex]
[tex] 900-60n+60=0 [/tex]
[tex] 960=60n [/tex]
[tex]n = 960\div60[/tex]
[tex]n = 16 [/tex]
Last month will be 16th
