📝 3.3 Homework: Variables & Arithmetic in Java

Learning Objectives

  1. Use variables in Java.
  2. Follow step-by-step sequencing.
  3. Use arithmetic operators (+, -, *, /).

Part 1: Simple Variables

Write a Java program that does the following:

  1. Create a variable grade1 and assign it the value 90.
  2. Create a variable grade2 and assign it the value 80.
  3. Calculate the average of grade1 and grade2 and store it in averageGrade.
  4. Display the average using System.out.println().

Example Output:
The average is 85.0

%%js

let grade1 = 90;
let grade2 = 80;
let averageGrade = (grade1 + grade2) / 2;
console.log("The average is " + averageGrade);

Part 2: Arithmetic Practice

Write a Java program to calculate these:

  1. num1 = 10
  2. num2 = 5
  3. sum = num1 + num2
  4. difference = num1 - num2
  5. product = num1 * num2
  6. quotient = num1 / num2
  7. Display all results using System.out.println().

Example Output:

Sum: 15
Difference: 5
Product: 50
Quotient: 2

%%js

let num1 = 10;
let num2 = 5;

let sum = num1 + num2;
let difference = num1 - num2;
let product = num1 * num2;
let quotient = num1 / num2;

console.log("Sum: " + sum);
console.log("Difference: " + difference);
console.log("Product: " + product);
console.log("Quotient: " + quotient);

Part 3: Step-by-Step Sequencing

Write a Java program that does this sequence:

  1. Set num1 = 2 and num2 = 3.
  2. Calculate num3 = num1 + num2.
  3. Calculate num4 = num3 * 2.
  4. Display num3 and num4 using System.out.println().

This shows sequencing: each step depends on the previous one.

%%js 

let n1 = 2;
let n2 = 3;
let n3 = n1 + n2;
let n4 = n3 * 2;

console.log("n3 = " + n3);
console.log("n4 = " + n4);

Part 4: Mixed Arithmetic

  1. Set a = 8, b = 4, c = 2.
  2. Calculate:
    • result1 = a + b * c
    • result2 = (a + b) * c
  3. Display result1 and result2 using System.out.println().

This helps practice order of operations.

%%js 

let a = 8;
let b = 4;
let c = 2;

let result1 = a + b * c;
let result2 = (a + b) * c;

console.log("Result 1: " + result1);
console.log("Result 2: " + result2);