Question

Write a Java method that computes the future investment value at a given interest rate for a specified number of years. Your method should return the future investment value after calculation.
The future investment is determined using the formula below:
    futureInvestmentValue = investmentAmount * (1+monthlyInterestRate)numberOfYears*12
You can use the following method header:
public static double futureInvestmentValue (double investmentAmount, double monthlyInterestRate, int years);

Answer 1

The required java method and the complete source code are given below.Detailed comments are included for better understanding the code.Screen shot of the code and output are also attached.If find any difficulty, feel free to ask in comment section. Please do upvote the answer.Thank you.

Method to calculate future investment value

public static double futureInvestmentValue(double investmentAmount, double monthlyInterestRate, int years)
{
    //calculating futureInvestmentValue
    //pow() method is used to find the power
    double futureInvestmentValue=investmentAmount *Math.pow((1+monthlyInterestRate),(years*12)) ;
    //returning the result
    return futureInvestmentValue;
}

Formula used

• futureInvestmentValue = investmentAmount * (1+monthlyInterestRate)^Years*12
• This is written in java using the statemernt futureInvestmentValue=investmentAmount *Math.pow((1+monthlyInterestRate),(years*12)) ;
• To find power,pow() function from Math class is used

Source code of the whole program

//Scanner class to read user input
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        //creating scanner object to read user input
        Scanner input=new Scanner(System.in);
        //prompt user to enter different values and read it using appropriate methods of Scanner class
        System.out.print("Enter Investment Amount: ");
        double amount=input.nextDouble();
        System.out.print("Enter Annual Interest : ");
        double annualRate=input.nextDouble();
        //calculating monthlyInterestRate in decimal form
        //dividing annualRate by 12 gives monthlyRate and dividing it by 100 gives its decimal form
        double monthlyRate=annualRate/1200;
        System.out.print("Enter Number of Years: ");
        int years=input.nextInt();
        //calling futureInvestmentValue()function
        double futureInvestValue=futureInvestmentValue(amount,monthlyRate,years);
        //printing the value
        System.out.printf("Future Investment Value: %.2f",futureInvestValue);
    }
    //futureInvestmentValue() function definition
    public static double futureInvestmentValue(double investmentAmount, double monthlyInterestRate, int years)
    {
        //calculating futureInvestmentValue
        //pow() method is used to find the power
        double futureInvestmentValue=investmentAmount *Math.pow((1+monthlyInterestRate),(years*12)) ;
        //returning the result
        return futureInvestmentValue;
    }
}

Screen shot of the code

Screen shot of the output