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Program that lists amount of weight in a given input

I am attempting to write a program that will list the amount of kilograms, grams, and milligrams in a given input. Ex. in the given input of 1050042mg, the output will say that there is 1 kilogram, 50 grams, and 42 milligrams.
import java.util.Scanner;
class milligrams {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int milligram;
double kilo, gram;
System.out.println("Enter the weight in milligrams: ");
milligram = in.nextInt();
kilo = milligram / 1000000;
gram = milligram / 10000;
milligram = milligram / 1;
System.out.println("The weight is " + kilo + "kilos, " + gram + "grams" + milligram + " milligrams");
}
}
The part I am struggling with is I believe I must change the 10-12 lines with code that will read the given user input and then divide the input by the appropriate number to get kg, g, and mg but I cannot figure out how to do it as I am new to java. I am aware the division numbers are incorrect but I don't believe that is the issue. If this is not the right approach please guide me to the right approach.

You can use the modulus (clock arithmetic) operator
const KG = 1000000;
const GRAM = 1000;
Scanner in = new Scanner(System.in);
int milligram;
double kilo, gram;
System.out.println("Enter the weight in milligrams: ");
milligram = in.nextInt();
kilo = milligram / KG;
//use the modulus here (and below)
milligram = milligram % KG;
gram = milligram / GRAM;
// 2nd use of modulus, this time with GRAN
milligram = milligram % GRAM;
System.out.println("The weight is " + kilo + "kilos, " + gram + "grams" + milligram + " milligrams");
}

Java, computing the following formula

I am trying the write the formula in the image using Java. However, I get the wrong output. This is what I am so far for the computation.
Assume Input is: Loan Amount = 50000 and Length = 3 year.
My output is currently "676.08" for 'Monthly Payment' and "25661.0" for "Total Interest Payment".
"Monthly payment" should be "1764.03" and "Total Interest Payment" should be "13505.05".
Code is:
//Program that displays the interest rate and monthly payment based on the loan amount and length of loan the user inputs.
import java.util.Scanner;
public class bankLoanSelection{
public static void main(String[] args){
Scanner input = new Scanner(System.in);
//Declarations.
double interestRate;
final double n = 12;
//Generates an account number in the range of 1 to 1000.
int accountnumber = (int)(Math.random() * 1000)+1;
//User input
System.out.print("Enter Loan Amount: $");
double L = input.nextDouble();
System.out.print("Length of Loan (years): ");
double i = input.nextDouble();
//selection structure using if and if-else statements.
if (L <= 1000)
interestRate = .0825;
else if (L <= 5000)
interestRate = .0935;
else if (L <= 10000)
interestRate = .1045;
else interestRate = .1625;
//Computations.
double MonthlyPayment = L * (interestRate / n) * Math.pow(1 + interestRate / n, i * n) / Math.pow(1 + interestRate / n, i * n) - 1;
double TotalAmountOfLoan = MonthlyPayment * i * n;
double TotalInterest = L - TotalAmountOfLoan;
//Output.
System.out.println("Account Number: #" + accountnumber);
System.out.println("Loan Amount: $" + L);
System.out.println("Loan Length (years): " + i);
System.out.println("Interest Rate: " + interestRate * 100 + "%");
System.out.printf("Total Monthly Payment: $%.2f%n", MonthlyPayment); //Rounds second decimal
System.out.println("Total Interest Payments: $" + TotalInterest);
}
}

You have to put round parentheses between condition.
It should be:
double MonthlyPayment = L * ((interestRate / n) * Math.pow(1 + interestRate / n, i * n))
/ (Math.pow(1 + interestRate / n, i * n) - 1);

You need to correct the arrangement of brackets in the denominator, the correct formula would be:
double numerator = L * (interestRate / n) * Math.pow(1 + interestRate / n, i * n)
double denominator = Math.pow(1 + interestRate / n, i * n) - 1;
double MonthlyPayment = numerator / denominator;
Try to break the problem into smaller units to solve.

Java - Least number of bills and coins for change

I have to do an assignment for my class that allows the user to key in two amounts - the first should be the total sale amount and the next would be the amount of change handed to the cashier. The program needs to calculate the change needed and tell the cashier how many of each monetary amount to return to the customer using the least number of bills and coins. Using $20, 10, 5, 1 and 0.25, 0.10, 0.05, and 0.01. I also need to include a while loop to make sure the cashier is given an amount greater than the amount due.
I have the following so far, but don't know where to go from here:
public class Change {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
//Enter sale amount less than $100
System.out.println("Enter the sale amount: ");
double price = input.nextDouble();
//Enter amount of money handed to cashier less than $100
System.out.println("Enter the amount of money handed to the cashier: ");
double payment = input.nextDouble();
double difference = payment - price;
int num20 = (int)(difference / 20);
System.out.println("num20 = " + num20);
difference = difference % 20;
System.out.println("difference = " + difference);
int num10 = (int)(difference / 10);
System.out.println("num20 = " + num10);
difference = difference % 10;
System.out.println("difference = " + difference);
int numQtr = (int)(difference / .25);
System.out.println("numqtr = " + numQtr);
int numDime = (int)(difference / .10);
System.out.println("numDime = " + numDime);
}

Use the mod operator and division to find values at each step
29 % 20 -> 9
(int) (29 / 20) -> 1
9 % 10 -> 9
(int) (9 / 10) -> 0
please note that casting the result of a division to an integer will truncate the returned value to a whole number.

Troubles with a math formula - Java

I'm making a program for my java class that calculates the population for a year given the start year (2011) and increases the population by 1.2% every year. The population for 2011 is 7.000 (I'm using decimals, instead of billions). I currently have this code.
int startYear = 2011;
int endYear = user_input.nextInt();
double t = 1.2; //Population percent increase anually
double nbr = (endYear - startYear); //Number of years increased
double pStart = 7.000; //Starting population of 2011
double pEnd = pStart * Math.exp(nbr * t); // Ending population of user input
DecimalFormat nf = new DecimalFormat("2");
System.out.println("Population in " + endYear + ": " (nf.format(pEnd)));
There's no errors in the code, everything works, but I'm having troubles with the pEnd equation. Currently when I enter 2016 for the end year, i get 22824. I've tried googling a formula, but i can't find anything. Do any of you guys have an idea of the formula? If you enter 2016 for the end year, it should be around 7.433

You're incrementing by a factor of 1.2, which would represent 120% instead of 1.2%. I think what you want is :
double t = 0.012;
This change gives me an exact value of 7.4328558258175175 from 2011 to 2016.
EDIT : here's the code as requested by the author :
public static void main(String args[]){
int startYear = 2011;
int endYear = 2016;
double t = 0.012; //Population percent increase anually
double nbr = (endYear - startYear); //Number of years increased
double pStart = 7.000; //Starting population of 2011
double pEnd = pStart * Math.exp(nbr * t); // Ending population of user input
System.out.println("Population in " + endYear + ": " + pEnd);
}

Use Math.pow(1 + t / 100, nbr) instead of Math.exp(nbr * t) because you need (1+t/100)^nbr (i.e. multiply 1 + t / 100 on itself nbr times), not exp^(nbr*t):
double pEnd = pStart * Math.pow(1 + t / 100, nbr); // Ending population of user input

Try this.
double pEnd = pStart * Math.pow(1.0 + t / 100, nbr);

Program will not do calculations

int single = 0, doub=0, triple=0, homer=0, atbats=0, totalbase, totalhits;
double slug, battingavg;
Scanner sc = new Scanner(System.in);
System.out.print("Enter singles (-1 to end): ");
single = sc.nextInt();
while (single != -1)
{
System.out.print("Enter doubles: ");
doub = sc.nextInt();
System.out.print("Enter triples: ");
triple = sc.nextInt();
System.out.print("Enter home runs: ");
homer = sc.nextInt();
System.out.print("Enter total at bats: ");
atbats = sc.nextInt();
System.out.print("Enter the player's name: ");
String name = sc.next();
totalbase = (single + doub * 2 + triple * 3 + homer * 4);
slug = totalbase / atbats;
battingavg = (single + doub + triple + homer) / atbats;
System.out.println("Player's name is " + name);
System.out.printf("The slugging percentage is %.3f\n", + slug);
System.out.printf("The batting percentage is %.3f\n", + battingavg);
System.out.print("Enter singles (-1 to end): ");
single = sc.nextInt();
}
This program will only output a 1 or a 0 after the calculations. Everything else works fine, but It just doesn't seem to do the calculations.

The problem is that when you do integer divisions, you'll get integer values. Instead use double or float data types. I see slug and battingavg are already doubles, but you're assigning the result of an integer division to them. If you cast at least one of the values in your calculations to a double you should get the output you expect. Example:
slug = totalbase / (double) atbats;
battingavg = (single + doub + triple + homer) / (double) atbats;

When you divide integer values and store the result in a double that is a widening conversion, but the value was calculate as an integer and thus you're widening the integer value.
Change this,
slug = totalbase / atbats;
battingavg = (single + doub + triple + homer) / atbats;
to something like this,
slug = ((double) totalbase / atbats);
battingavg = ((double) (single + doub + triple + homer) / atbats);
to get double values into your double variables.