Question: Create a Java file called CompoundInterestYourLastName. Write a method called computeBalance( ) that computes the balance of a bank account with a given initial deposit,
Create a Java file called CompoundInterestYourLastName. Write a method called computeBalance( ) that computes the balance of a bank account with a given initial deposit, annual interest rate, after a given number of years for the investment. Assume interest is compounded yearly.
The formula for determining compound interest (compounded yearly) is:
where:
- A = the future value of the investment/loan, including interest
- P = the principal investment amount (the initial deposit or loan amount)
- r = the annual interest rate (decimal)
- t = the time the money is invested or borrowed for
Create your method to accept three parameters in this order: initial deposit, annual interest rate as a decimal, after a given number of years.
Your method should return a double value of the future value including interest.
In your main method, run the following tests to verify your method is working correctly.
System.out.printf("Your total is $%.2f", computeBalance(5000, .05, 10));
// should return $8144.47
System.out.printf(" Your total is $%.2f", computeBalance(2000, .03, 5));
// should return $2318.55
System.out.printf(" Your total is $%.2f", computeBalance(3000, .01, 10));
// should return $3313.87
Pay close attention to your parameters to make sure they match the test data!
*Note: Your methods should have this exact signature line, including the correct spelling, capitalization and parameter types. Otherwise, when I run the test to check the file, your methods will fail and you'll have to revise.
assertEquals(double expected, double actual, double delta); Asserts that two doubles or floats are equal to within a positive delta.
If you ran your methods (with the main method without the printf( )), you'll see that you get several decimal points. One way that we can account for small differences is by giving the assertEquals method a delta - 0.01. This means that if the return result is within 0.01 of the expected value, return true. The assertion method would look something like:
assertEquals(expected, actual, 0.01);
Write assertion methods for the three examples below. Make sure that your assertion methods all pass.
System.out.printf("Your total is $%.2f", computeBalance(1000, .045, 3));
// should return $1141.17
System.out.printf(" Your total is $%.2f", computeBalance(2000, .03, 5));
// should return $2318.55
System.out.printf(" Your total is $%.2f", computeBalance(3000, .01, 10));
// should return $3313.87
Step by Step Solution
There are 3 Steps involved in it
Get step-by-step solutions from verified subject matter experts
