SOLUTION: Calculate selling price of a house if: They paid 21082.00 down payments are 682.00 per month for 30 years interest rate 6.6% is compounded monthly

Algebra ->  Finance -> SOLUTION: Calculate selling price of a house if: They paid 21082.00 down payments are 682.00 per month for 30 years interest rate 6.6% is compounded monthly      Log On


   



Question 1203536: Calculate selling price of a house if:
They paid 21082.00 down
payments are 682.00 per month for 30 years
interest rate 6.6% is compounded monthly

Found 2 solutions by Theo, ikleyn:
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the amount of the loan is 106786.28
add to that the down payment of 21082 to get a total sale price of 127868.28.
here are the results from the calculator that i used.

the inputs to this calculator were:
present value = -
future value = 0
number pf time periods = 30 * 12 = 360 months.
payment amount per time period = -682
interest rate per time period = 6.6% / 12 = .55%
payments are made at the end of each time period.
i clicked on present value.
the calculator came back with a present value of 106786.28.
that was the amount of the loan.
the calculator that i used can be found at https://arachnoid.com/finance/

Answer by ikleyn(52805) About Me  (Show Source):
You can put this solution on YOUR website!
.
Calculate selling price of a house if:
They paid 21082.00 down
payments are 682.00 per month for 30 years
interest rate 6.6% is compounded monthly
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        This my solution goes second after the solution by @Theo.
        @Theo used an online calculator in his solution.
        Since this web-site is to teach Math, the expected solution should be mathematical.
        So, I present here a standard mathematical solution.
        Calculator can be used as a secondary tool for verification.
        Then the sequence of steps would be normally educative.


In this problem, we are given the monthly payment for the loan;
the annual interest rate and the duration of the loan.


Having this input information, we can find the loaned amount.


Use the formula for the monthly payment for a loan

    M = L%2A%28r%2F%281-%281%2Br%29%5E%28-n%29%29%29


where L is the loan amount; r  is the effective interest rate per month;
n is the number of payments (same as the number of months); M is the monthly payment.


From this formula, express for the loan amount 

    L = M%2F%28%28r%2F%281-%281%2Br%29%5E%28-n%29%29%29%29.


In this problem  M = $682;  r = 0.066%2F12,  n = 30*12 = 360 monthly payments.


Substitute these values into the formula and get for the maximum loan amount

    L = 682%2F%28%28%280.066%2F12%29%2F%281-%281%2B0.066%2F12%29%5E%28-360%29%29%29%29 = $106,786.28.


To find the celling price of the house, we should add the down payment to this value

    the celling price = $106,786.28 + $21,082.00 = $127,868.281


ANSWER.  The selling price of the house is $127,868  (rounded to the closest dollar).

Solved.

Notice that my numbers precisely coincide with the numbers in the post by @Theo, so you can consider it as a check.


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In such calculations, it is important to avoid intermediate rounding.
Rounding can be done at the end, only.
Intermediate rounding is PROHIBITED, since it leads to wrong answer.

Also, a calculator should provide the necessary precision.

I use MS Excel in my computer. It works with 15 decimals in mantissa
and provides the necessary precision.

I simply copy-paste my numerical formula into Excel spreadsheet and get the answer in one click.

Many standard online calculators provide the necessary precision.

You may use, for example, this free-of-charge online calculator

https://www.calculatorsoup.com/calculators/financial/loan-calculator.php

It is reliable, has convenient user-friendly interface, has complete instructions and descriptions,
provides the necessary precision and was checked million times. You may use it to check my/your calculations.


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There is another (= one more) reason why I produced and placed my solution here.

@Theo' posts used visual plots to support his solutions.
These plots were integral inseparable part of his solutions.
But some time ago, Theo left this forum and stopped supporting web-site with his plots.
As a result, you see now some colored spots in his posts, where his plots should be.
Due to this reason, @Theo's posts lost their educational meaning and value.
Therefore, I create my posts with my own mathematical solutions
to replace @Theo' solutions and provide meaningful mathematical content.