Hey guys, I'm trying to create a program that has three items and adds the cost of the three items and prints the final total with sales tax. I need a subtotal, sales tax, and total amount. I'm having a problem getting the program to calculate the quantity correctly and run and I also am using the printf command so it can be rounded to two decimal places but i cant get it to work. Help anyone??

import java.util.*;

public class CashRegister
{


public static void main(String[] args)
{
//Declaring variables
double Item1, Item2, Item3;
double ItemPrice1, ItemPrice2, ItemPrice3;
double Subtotal, SalesTax, TotalAmount;

//Allowing keyboard input so I can print to the screen
Scanner keyboard = new Scanner(System.in);

System.out.println("Enter Quantity of first item: ");
Item1 = keyboard.nextDouble();

System.out.println("Enter the price of the first item: $ ");
ItemPrice1 = keyboard.nextDouble();

System.out.println("Enter Quantity of the second item: ");
Item2 = keyboard.nextDouble();

System.out.println("Enter the price of the second item: $ ");
ItemPrice2 = keyboard.nextDouble();

System.out.println("Enter Quantity of the third item: ");
Item3 = keyboard.nextDouble();

System.out.println("Enter the price of the third item: $ ");
ItemPrice3 = keyboard.nextDouble();

//Total of all three items before sales tax is added
Subtotal = ItemPrice1 + ItemPrice2 + ItemPrice3;

//Sales tax of 7% multiplied to the Subtotal
SalesTax = Subtotal * 0.07;

//Total amount which is the Subtotal plus the added 7% tax rate
TotalAmount = Subtotal + SalesTax;

System.out.printf("Subtotal: $%.2f \n"+ Subtotal);

System.out.printf("Sales Tax: $%.2f \n" + SalesTax);

System.out.printf("Total Amount: $%.2f \n" + TotalAmount);

The First problem is that you have not posted a program that will compile.
Can you fix that?

If you get your program to compile, it should work. There are a few things you need to be mindful of though:

1. Why are your quantity variables doubles? Can you buy 2.75 of a certain object?
2. You're using the Scanner method .nextDouble(). If this is just an exercise, that's OK, but it's still good practice to write foolproof code - what happens if the user types in an int, or a String?

Hey I got it to compile and it is correct but I need help to get two decimal places for the subtotal, salestax and total amount but i dont know how to do it, here are the given steps if you are willing to help me.

1. multiply the amount by 100
------------ Example: --- 1.7948 would become 179.48
2. add 0.5 to the result
------------ Example: --- 179.48 + 0.5 = 179.98
3. type cast the answer as an integer
------------ Example: --- 179.98 type cast as an integer gives 179
4. divide the resulting integer by 100 to put the two decimal places back where they should be
------------ Example: --- 179 becomes 1.79

It also says to use this statement to get the rounding:

System.out.printf("Subtotal: $%.2f \n", subTotal);

import java.util.*;

public class CashRegister 
{

	
	public static void main(String[] args) 
	{
		//Declaring variables 
		int item1, item2, item3;
		double itemPrice1, itemPrice2, itemPrice3;
		double subTotal, salesTax , totalAmount;
		
		
		//Allowing keyboard input so I can print to the screen
		Scanner keyboard = new Scanner(System.in);
		
		System.out.print("Enter Quantity of first item: ");
		item1 = keyboard.nextInt();
		
		System.out.print("Enter the price of the first item: $");
		itemPrice1 = keyboard.nextDouble();
		
		System.out.print("Enter Quantity of the second item: ");
		item2 = keyboard.nextInt();
		
		System.out.print("Enter the price of the second item: $");
		itemPrice2 = keyboard.nextDouble();
		
		System.out.print("Enter Quantity of the third item: ");
		item3 = keyboard.nextInt();
		
		System.out.print("Enter the price of the third item: $");
		itemPrice3 = keyboard.nextDouble();
		
		//Total of all three items before sales tax is added
		subTotal = itemPrice1 * item1 + itemPrice2 * item2 + itemPrice3 * item3;
				
		//Sales tax of 7% multiplied to the subtotal
		salesTax = subTotal * 0.07;
		
		//Total amount which is the subtotal plus the added 7% tax rate
		totalAmount = subTotal + salesTax;
		
		System.out.printf("Subtotal: $" + subTotal);
		
		System.out.printf("Sales Tax: $" + salesTax);
		
		System.out.printf("Total Amount: $" + totalAmount);

Oh yea I have use these numbers to make the result look like this with the exact numbers, i highlighted the sales tax because thats what those 4 steps were talking about

Enter the quantity of the first product: 3
Enter the price of the first product: $5.25
Enter the quantity of the second product: 2
Enter the price of the second product: $1.83
Enter the quantity of the third product: 7
Enter the price of the third product: $0.89

Subtotal: $25.64
Sales Tax: $1.79
Total Due: $27.43

But you just posted the steps you need to do, to solve that problem. I don't quite understand what you are asking.

Yes those are not my answers, those are the same numbers i need to use for my assignment and it needs to look exactly that way, i copyed and pasted from the assignment of what my result should look like with those numbers

For Example, what im saying is my answers look like 25.64353636,1.794838252, 27.34253636 not 25.64, 1.79, 27.43

Then just use the $%.2f\n...which casts to a float with 2 decimal places.

System.out.printf("Subtotal: $%.2f\n" + subTotal);
System.out.printf("Sales Tax: $%.2f \n" , salesTax);
System.out.printf("Total Amount: $%.2f \n" ,totalAmount);

Edited 6 Years Ago by Akill10: n/a

I know but im getting an error that looks like this

Subtotal: $Exception in thread "main" java.util.MissingFormatArgumentException: Format specifier '.2f'
at java.util.Formatter.format(Unknown Source)
at java.io.PrintStream.format(Unknown Source)
at java.io.PrintStream.printf(Unknown Source)
at CashRegister.main(CashRegister.java:46)

Getting an error though when i do it

Subtotal: $Exception in thread "main" java.util.MissingFormatArgumentException: Format specifier '.2f'
at java.util.Formatter.format(Unknown Source)
at java.io.PrintStream.format(Unknown Source)
at java.io.PrintStream.printf(Unknown Source)
at CashRegister.main(CashRegister.java:46)

I know but im getting an error that looks like this

Subtotal: $Exception in thread "main" java.util.MissingFormatArgumentException: Format specifier '.2f'
at java.util.Formatter.format(Unknown Source)
at java.io.PrintStream.format(Unknown Source)
at java.io.PrintStream.printf(Unknown Source)
at CashRegister.main(CashRegister.java:46)

Thats caused by using the wrong syntax with the print format. System.out.printf(); cannot be used the same way as print() or println().

printf (String format, Object... args)

Where the format is the $%.2f in your case. The '%' sign signals it is a specifier. The precision value 2 requires two places in the fraction, and the conversion symbol 'f' indicates a decimal representation of a floating-point number.

So, the thing you are doing wrong, is using a + in your print statement.

System.out.printf("Sales Tax:  $%.2f \n" [U],[/U] salesTax);

Edited 6 Years Ago by Akill10: n/a

Thats caused by using the wrong syntax with the print format. System.out.printf(); cannot be used the same way as print() or println().

printf (String format, Object... args)

Where the format is the $%.2f in your case. The '%' sign signals it is a specifier. The precision value 2 requires two places in the fraction, and the conversion symbol 'f' indicates a decimal representation of a floating-point number.

So, the thing you are doing wrong, is using a + in your print statement.

System.out.printf("Sales Tax:  $%.2f \n" [U],[/U] salesTax);

AAAAAAAAAhhhhhhhh omg im an idiot, thanks man I would have never seen that

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