Question

CENGAGE MINDTAP gramming Exercise 3-8 PaintCalculator.java Instructions Assume that a gallon of paint covers about 350 square feet of wall space. Create an application with a main() method that prompts the user for the length, width, and height of a rectangular room. Pass these three values to a method that does the following: 1 import java.util.Scanner; 2 public class PaintCalculator { 3 public static void main(String args[]) { // Write your code here public static double computeArea double length, double width, double height) { // Write your code here 18 public static double computeGallons(double area) { // Write your code here 13) • Calculates the wall area for a room • Passes the calculated wall area to another method that calculates and returns the number of gallons of paint needed • Displays the number of gallons needed • Computes the price based on a paint price of $32 per gallon, assuming that the painter can buy any fraction of a gallon of paint at the same price as a whole gallon • Returns the price to the nain() method The main() method displays the final price. For example: You will need 2.0 gallons OT

Answer 1

Here is the solution to the above question. The explanation is done in the code itself in the form of comments (see image) for better line by line explanation and better understanding.

Code:

import java.util.Scanner;  
public class PaintCalculator{                                                               // main class
   public static void main (String args[]){
       int length,width,height;                                                           // variable decleration for length, width and height.
       double area,gallon;                                                                   // variable for area and gallon
       System.out.print("\nEnter the length of the room: ");                               // user input
       Scanner s = new Scanner(System.in);       
        length = s.nextInt();
       System.out.print("\nEnter the width of the room: ");                               // user input
       Scanner s2 = new Scanner(System.in);
        width = s2.nextInt();
       System.out.print("\nEnter the height of the room: ");                               // user input
       Scanner s3 = new Scanner(System.in);
        height = s3.nextInt();
       area=computeArea(length,width,height);                                                // calling computeArea function and storing the return value in area.
       gallon=computeGallons(area);                                                       // calling computeGallons function and storing the return value in gallon.
       double total_cost=gallon*32;                                                        // calculating total cose
       System.out.println("\nYou will need "+String.format("%.2f", gallon)+" gallons.");   // showing the gallons
       System.out.println("\nTotal cost will be "+String.format("%.2f", total_cost)+"."); // showing the total cost.
   }
  
   public static double computeArea(double length,double width,double height){            // function computeArea decleration
       return (length*height*2+height*width*2);
   }
  
   public static double computeGallons(double area){                                        // function computeGallons decleration
       return (area/350);
   }
}

Output:

How to Run program:

• Copy the code given above into a file and save the file as PaintCalculator.java.
• Open your command window, navigate to the same directory as the file saved.
• Enter the following command

javac PaintCalculator.java

then

java PaintCalculator

done.

Note: If you are still unable to understand, then comment with it and I will be happy to help.