Chapter 1 Exercise 11, Introduction to Java Programming, Tenth Edition Y. Daniel LiangY.

(Population projection) The U.S. Census Bureau projects population based on the following assumptions:
 ■ One birth every 7 seconds
 ■ One death every 13 seconds
 ■ One new immigrant every 45 seconds
 Write a program to display the population for each of the next five years. Assume the current population is 312,032,486 and one year has 365 days. Hint: In Java, if two integers perform division, the result is an integer. The fractional part is truncated. For example, 5 / 4 is 1 (not 1.25) and 10 / 4 is 2 (not 2.5). To get an accurate result with the fractional part, one of the values involved in the division must be a number with a decimal point. For example, 5.0 / 4 is 1.25 and 10 / 4.0 is 2.5.

public class Exercise_11 {

    public static void main(String[] strings) {

        double birthRateInSeconds = 7.0;
        double deathRateInSeconds = 13.0;
        double newImmigrantInSeconds = 45.0;



        double currentPopulation = 312032486;

        double secondsInYears = 60 * 60 * 24 * 365;

        double numBirths = secondsInYears / birthRateInSeconds;
        double numDeaths = secondsInYears / deathRateInSeconds;
        double numImmigrants = secondsInYears / newImmigrantInSeconds;

        for (int i = 1; i <= 5; i++) {
            currentPopulation += numBirths + numImmigrants - numDeaths;
            System.out.println("Year " + i + " = " + (int)currentPopulation);

        }


    }
}