document.write( "Question 1189735: A person purchased a ​$198741 home 10 years ago by paying ​20% down and signing a​ 30-year mortgage at 11.4​% compounded monthly. Interest rates have dropped and the owner wants to refinance the unpaid balance by signing a new 20​-year mortgage at compounded 6.6% monthly. How much interest will refinancing​ save?\r
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\n" ); document.write( "\n" ); document.write( "Please Help! Thank you :)
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Algebra.Com's Answer #821488 by math_tutor2020(3817)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "I'm using the formulas found on this page
\n" ); document.write( "https://www.mtgprofessor.com/formulas.htm\r
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\n" ); document.write( "\n" ); document.write( "The home value is $198,741.
\n" ); document.write( "20% of it is paid off through the downpayment, so 80% is remaining
\n" ); document.write( "0.80*198741 = 158,992.80\r
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\n" ); document.write( "\n" ); document.write( "This is the loan amount L
\n" ); document.write( "L = 158,992.80\r
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\n" ); document.write( "\n" ); document.write( "For the original mortgage at 11.4%, the monthly rate c is
\n" ); document.write( "c = r/12 = 0.114/12 = 0.0095
\n" ); document.write( "and the number of months is n = 360 because 30*12 = 360.\r
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\n" ); document.write( "\n" ); document.write( "So,
\n" ); document.write( "L = 158,992.80
\n" ); document.write( "c = 0.0095
\n" ); document.write( "n = 360
\n" ); document.write( "Plug those values into the first formula mentioned in that link above. You should get a monthly payment of P = 1562.37\r
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\n" ); document.write( "\n" ); document.write( "Plug those values into the second formula along with lowercase p = 120 (since 10 years = 120 months) to find that B = 147,456.55
\n" ); document.write( "Unfortunately that link uses uppercase P to represent payment and lowercase p to denote the number of months paid into; the letter choice may seem a bit confusing. \r
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\n" ); document.write( "\n" ); document.write( "Anyways, we get B = 147,456.55 which is the unpaid balance at year 10. This is the starting point, and we'll have two branching options\r
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\n" ); document.write( "\n" ); document.write( "starting balance = 147,456.55\r
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\n" ); document.write( "\n" ); document.write( "Mortgage A (interest rate = 11.4%)
\n" ); document.write( "monthly payment = 1562.37
\n" ); document.write( "total amount paid back = (240 months)*(1562.37 per month) = 374,968.80
\n" ); document.write( "m = Total interest paid
\n" ); document.write( "m = 374,968.80 - 147,456.55
\n" ); document.write( "m = 227,512.25\r
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\n" ); document.write( "\n" ); document.write( "Mortgage B (interest rate = 6.6%)
\n" ); document.write( "monthly payment = 1108.09
\n" ); document.write( "total amount paid back = (240 months)*(1108.09 per month) = 265,941.60
\n" ); document.write( "n = Total interest paid
\n" ); document.write( "n = 265,941.60 - 147,456.55
\n" ); document.write( "n = 118,485.05\r
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\n" ); document.write( "\n" ); document.write( "m-n = amount of interest saved by going with mortgage B
\n" ); document.write( "m-n = 227,512.25 - 118,485.05
\n" ); document.write( "m-n = 109,027.20\r
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\n" ); document.write( "\n" ); document.write( "Answer: $109,027.20
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