Question 1202789
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I'll be using the 2nd formula mentioned at this link
<a href="https://www.mtgprofessor.com//formulas.htm">https://www.mtgprofessor.com//formulas.htm</a>


That formula is
B = L*( (1+c)^n - (1+c)^p )/( (1+c)^n - 1 )
it calculates the remaining balance. 
It's the amount still owed at any given month p.


We have a giant single fraction
numerator = L*((1+c)^n - (1+c)^p)
denominator = (1+c)^n - 1


Variables
L = loan amount
c = monthly interest rate in decimal form
n = number of months of entire mortgage
p = current month number


We have
L = 150,000
c = 0.03/12 = 0.0025 exactly
n = 12*15 = 180 months (equivalent to 15 years)
p = 12*5 = 60 months (equivalent to 5 years)


Let's calculate the remaining balance
B = L*( (1+c)^n - (1+c)^p )/( (1+c)^n - 1 )
B = 150000*( (1+0.0025)^180 - (1+0.0025)^60 )/( (1+0.0025)^180 - 1 )
B = 107276.767971557
B = 107276.77


The amortization table on this calculator
<a href="https://www.calculator.net/loan-calculator.html">https://www.calculator.net/loan-calculator.html</a>
can be used to verify the answer.


Answer: <font color=red>$107,276.77</font>
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