for (initialization; condition; update)
   statement

Equivalent to

initialization;
while (condition)
{
  statement;
  update;
}

Example:  Add one more method to Investment class
/**
    Keeps accumulating interest for a given number of years.
    @param n the number of years
 */
 public void waitYears(int n)
 {
    for (int i = 1; i <= n; i++)
    {
       double interest = balance * rate / 100;
       balance = balance + interest;
    }
    years = years + n;
 }

import java.util.Scanner;

public class Sum
{
   public static void main(String[] args)
   {
     int A, total=0;
     Scanner in = new Scanner(System.in);
     for(int i=0; i<5; i++)
     {
       System.out.println("Enter a number");
       A = in.nextInt(); 
       total = total + A;  //total += A;
     }
     System.out.println('\n'+ "The total is "+ total + ".");
   }
}

You have to initialize TOTAL as 0.
Repeat using A box to get new data.  Previous data will be erased.
Accumulate total of numbers by an assignment statement as
TOTAL = TOTAL +A;
or
TOTAL += A;

A semicolon that shouldn't be there: