Thread: Monthly mortgage payment calculator

ok when i run this program it asks questions i enter the following
house price = 1000
down payment = 50
interest rate = .05
number of payments 30
top equation: double tempTop = ((housePrice - downPayment) * (annualInterestRate/12));
bottom equation: double tempBottom = ((1-(1+(Math.pow(annualInterestRate/12, -numberofPayments)))));
double monthlyPayment = (tempTop / tempBottom);



the end results are top equation = 3.9583333333333335
end result for bottom equation = -2.548808761537613E71 negative number
mortgage payment = top/bottom = -1.5530130753887556E-71 negative number

what will that accomplish i dont get what your trying to do i showed you the formula and i showed you how i broke it down what else needs to be done?

its in bottom expression but i dont know how to fix it thats problem i can break it down all day long but something is wrong please help me!!!!!!!!!!

i dont know how to break this line down any further

 
double tempBottom = ((1-(1+(Math.pow(annualInterestRate/12, -numberofPayments)))));

on paper sure in java no clue

forget it im struggling for hours now and all your doing is asking me more questions. thanks for nothing its much appreciated

i apologize just frustrated I think i figured it

double tempBottom = ((1-(Math.pow(1+(annualInterestRate/12), -numberofPayments))));

my 1+ was in the wrong spot, Norm you were right when i broke it completely down i saw it thanks

--- Update ---

 
 
import java.util.Scanner;
 
	public class Project1 {
	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
 
		System.out.println("Enter the price of the house: ");
		double housePrice = input.nextDouble();
		System.out.println("Enter the down payment: ");
		double downPayment = input.nextDouble();
		System.out.println("Enter the annual interest rate: ");
		double annualInterestRate = input.nextDouble();
		System.out.println("Enter the number of payments: ");
		double numberofPayments = input.nextDouble();
 
 
		double tempTop = ((housePrice - downPayment) * (annualInterestRate/12));
		double tempBottom = ((1-(Math.pow(1+(annualInterestRate/12), -numberofPayments))));
		double monthlyPayment = (tempTop / tempBottom);
 
		System.out.println( "The price of the house is: " + housePrice);
		System.out.println( "Your down payment is : " + downPayment);
		System.out.println( "Your annual interest rate is :" + annualInterestRate);
		System.out.println( "Your number of payments are: " + numberofPayments);		
		System.out.println( "Your monthly payment is: " + monthlyPayment);
		System.out.println( "");
		System.out.println( "Top of equation equals: " + tempTop);
 
		System.out.println( "Bottom of equation equals: " + tempBottom);
 
 
 
	}	
	}

i think im on track please check

Originally Posted by iamgonge

i dont know how to break this line down any further

 
double tempBottom = ((1-(1+(Math.pow(annualInterestRate/12, -numberofPayments)))));

on paper sure in java no clue

Norm is trying to help you to help yourself. You can't learn something if people just give you the answer. Especially in programming. Now look at this line off code I quoted and look at how the math.pow method works. Do you see a problem.

Norm is correct when he tells you to "continue breaking the compound expressions down into single expressions". This helps you to find if your calculations are wrong and were they are going wrong. For example :
3*(35+(50/5)) - to break this down
3*(35+10)
3*45
ANS = 135

thank you