Answer; Part (A)

Current Monthly Installment Amount =

No of Year = 25 Years

No of period = 25 X 12 = 300 monthly payments

Rate = 10% per annum

Monthly rate = 10 % / 12 = .8333%

Principal Amount = $ 100,000

Formula ; Monthly Installment = = P × r × (1 + r)n/((1 + r)^n - 1)

= 100,000 x .83333% [ (1.0083333)^300/ (1.008333)^300 -1]

= 833.33 x[12.05682545/(12.05682545-1)]

= 833.33 X 1.090441873

= $908.70 Per Month or $$909

Answer Part B

Ramaining Amount After 10 years = Formula

Ramaining Amount =

= 100000*(1.0083333)^120 - 908.70*[(1.008333)^120 - 1]/.008333

= 100000*2.707030752 - 908.70*[2.707030752 - 1]/.008333

= 100000*2.707030752 - 908.70*[1.707030752]/.008333

=270703.0752 - 908.70*204.8445096

=270703.0752-186142.2059

= $84560.87 or $84561

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