Instructions: Create variables to store a student's name, age, and an array of grades. Print each value to the console with a label. Example output should look like:
// Student: John Doe // Age: 18 // Grades: 85, 90, 78, 92
var studentName = "John Doe";
var studentAge = 18;
var studentGrades = [85, 90, 78, 92];
console.log("Student:", studentName);
console.log("Age:", studentAge);
console.log("Grades:", studentGrades.join(", "));
Instructions: Demonstrate how JavaScript treats
strings and numbers differently. Create two variables: one string
("5") and one number (2). Print the result
of adding and subtracting them using console.log().
Explain why the results are different.
var num1 = "5";
var num2 = 2;
console.log("String + Number:", num1 + num2); // "52" (string)
console.log("String - Number:", num1 - num2); // 3 (number)
Instructions: Write code to convert temperatures
between Celsius and Fahrenheit. First, convert 25°C to Fahrenheit and
print the result. Then convert 77°F to Celsius and print the result.
Use formulas: °C = (°F - 32) × 5/9 °F = (°C × 9/5) + 32
var celsius = 25;
var fahrenheit = (celsius * 9 / 5) + 32;
console.log(celsius + "°C = " + fahrenheit + "°F");
fahrenheit = 77;
celsius = (fahrenheit - 32) * 5 / 9;
console.log(fahrenheit + "°F = " + celsius.toFixed(2) + "°C");
Instructions: Create a simple calculator using
variables. Assign two numbers (a and b) and
an operator ('+', '-', '*', or
'/'). Use if/else to perform the operation and print the
result to the console.
var a = 10;
var b = 5;
var operation = '*';
var result;
if (operation === '+') result = a + b;
else if (operation === '-') result = a - b;
else if (operation === '*') result = a * b;
else if (operation === '/') result = a / b;
else result = "Invalid operation";
console.log(a + " " + operation + " " + b + " = " + result);Instructions: Write a function that takes an amount in one currency and converts it to another using an exchange rate. Test the function by converting 100 USD to Euros at a rate of 0.91. Print the result.
function convertCurrency(amount, rate) {
return (amount * rate).toFixed(2);
}
var usd = 100;
var rate = 0.91;
console.log(usd + " USD = €" + convertCurrency(usd, rate));Instructions: Write a function that takes a student's score (number out of 100) and returns a grade based on these rules: 90+ = A, 80+ = B, 70+ = C, 60+ = D, below 60 = F. Test it with a score of 87 and print the result.
function getGrade(score) {
if (score >= 90) return "A";
if (score >= 80) return "B";
if (score >= 70) return "C";
if (score >= 60) return "D";
return "F";
}
console.log("Grade:", getGrade(87));Instructions: Write a function that takes a number and prints whether it is positive, negative, or zero, and whether it is even or odd.
function classifyNumber(num) {
var type = num > 0 ? "Positive" : num < 0 ? "Negative" : "Zero";
var parity = num % 2 === 0 ? "Even" : "Odd";
console.log(num + " is " + type + " and " + parity);
}
classifyNumber(-7);Instructions: Write a function that checks if a given year is a leap year. A year is a leap year if it is divisible by 4 but not by 100, unless it is also divisible by 400. Test your function with the year 2024 and print the result.
function isLeapYear(year) {
if ((year % 4 === 0 && year % 100 !== 0) || (year % 400 === 0)) {
return true;
}
return false;
}
console.log("Leap Year?", isLeapYear(2024));Instructions: Given an array of marks, write code to find the total, average, highest, lowest marks, and count how many passed (mark ≥ 60). Print all these values to the console.
var marks = [78, 82, 93, 67, 55, 76, 89, 91, 68, 72];
var total = 0;
var highest = marks[0];
var lowest = marks[0];
var passed = 0;
for (var i = 0; i < marks.length; i++) {
total += marks[i];
if (marks[i] > highest) highest = marks[i];
if (marks[i] < lowest) lowest = marks[i];
if (marks[i] >= 60) passed++;
}
var average = total / marks.length;
console.log("Total:", total);
console.log("Average:", average.toFixed(2));
console.log("Highest:", highest);
console.log("Lowest:", lowest);
console.log("Passed:", passed);
Instructions: Write a function that takes an array of
numbers and returns the sum, average, maximum, and minimum values.
Test it with the array [10, 20, 30, 40] and print the
result.
function analyzeArray(arr) {
var sum = 0;
var max = arr[0];
var min = arr[0];
for (var i = 0; i < arr.length; i++) {
sum += arr[i];
if (arr[i] > max) max = arr[i];
if (arr[i] < min) min = arr[i];
}
var avg = sum / arr.length;
return { sum: sum, average: avg, max: max, min: min };
}
console.log(analyzeArray([10, 20, 30, 40]));Instructions: Given an array of cart items (each with name, price, and quantity), print the total cost for each item and the overall subtotal, tax (5%), and final total.
var cart = [
{ item: "Laptop", price: 999.99, quantity: 1 },
{ item: "Headphones", price: 129.50, quantity: 2 },
{ item: "Mouse", price: 25.75, quantity: 1 }
];
var subtotal = 0;
for (var i = 0; i < cart.length; i++) {
var total = cart[i].price * cart[i].quantity;
subtotal += total;
console.log(cart[i].item + " x" + cart[i].quantity + " = $" + total.toFixed(2));
}
var tax = subtotal * 0.05;
var finalTotal = subtotal + tax;
console.log("Subtotal:", subtotal.toFixed(2));
console.log("Tax:", tax.toFixed(2));
console.log("Total:", finalTotal.toFixed(2));
Instructions: Write a function that takes an array
and an operation ("square", "double", "half") and returns a new array
after applying the operation to each element. Test with the array
[1,2,3] and operation "square".
function transformArray(arr, operation) {
var result = [];
for (var i = 0; i < arr.length; i++) {
if (operation === "square") result.push(arr[i] * arr[i]);
else if (operation === "double") result.push(arr[i] * 2);
else if (operation === "half") result.push(arr[i] / 2);
}
return result;
}
console.log(transformArray([1, 2, 3], "square"));
Instructions: Given an array of student objects (with
id, name, and marks array),
calculate and add total and average marks for each student. Print the
top student (highest average) and print names of all students with
average above 80.
var students = [
{ id: 1, name: "Ali", marks: [85, 90, 78] },
{ id: 2, name: "Fatima", marks: [92, 86, 93] },
{ id: 3, name: "Sara", marks: [70, 75, 80] }
];
for (var i = 0; i < students.length; i++) {
var sum = 0;
for (var j = 0; j < students[i].marks.length; j++) {
sum += students[i].marks[j];
}
students[i].total = sum;
students[i].average = sum / students[i].marks.length;
}
var topStudent = students[0];
for (var i = 1; i < students.length; i++) {
if (students[i].average > topStudent.average) {
topStudent = students[i];
}
}
console.log("Top Student:", topStudent.name);
var threshold = 80;
for (var i = 0; i < students.length; i++) {
if (students[i].average > threshold) {
console.log("Above threshold:", students[i].name);
}
}
Instructions: Create an inventory array of objects
(with id, name, price,
quantity). Write functions to add an item, update
quantity, calculate total inventory value, and return items below a
given stock threshold.
var inventory = [
{ id: 101, name: "Notebook", price: 12.99, quantity: 50 },
{ id: 102, name: "Pen Set", price: 7.50, quantity: 100 },
{ id: 103, name: "Stapler", price: 8.25, quantity: 30 }
];
function addItem(item) {
inventory.push(item);
}
function updateQuantity(id, change) {
for (var i = 0; i < inventory.length; i++) {
if (inventory[i].id === id) {
inventory[i].quantity += change;
}
}
}
function totalInventoryValue() {
var total = 0;
for (var i = 0; i < inventory.length; i++) {
total += inventory[i].price * inventory[i].quantity;
}
return total;
}
function lowStock(threshold) {
var result = [];
for (var i = 0; i < inventory.length; i++) {
if (inventory[i].quantity < threshold) {
result.push(inventory[i]);
}
}
return result;
}Instructions: Create a bank account object with properties for owner, balance, and transactions. Write functions to deposit, withdraw, get the balance, and view transaction history. Print test results for each function.
var account = {
owner: "Sara Ahmed",
balance: 1000,
transactions: []
};
function deposit(amount) {
account.balance += amount;
account.transactions.push({ type: "deposit", amount: amount });
}
function withdraw(amount) {
if (amount > account.balance) {
console.log("Insufficient funds");
return;
}
account.balance -= amount;
account.transactions.push({ type: "withdraw", amount: amount });
}
function getBalance() {
return account.balance;
}
function getHistory() {
return account.transactions;
}Instructions: Create a simple to-do list using an array of task objects. Write functions to add a new task, mark a task as complete, delete a task, and list all, completed, or pending tasks. Print sample outputs for each function.
var tasks = [
{ id: 1, description: "Complete assignment", completed: false },
{ id: 2, description: "Review notes", completed: true }
];
function addTask(desc) {
tasks.push({ id: tasks.length + 1, description: desc, completed: false });
}
function markComplete(id) {
for (var i = 0; i < tasks.length; i++) {
if (tasks[i].id === id) {
tasks[i].completed = true;
}
}
}
function deleteTask(id) {
for (var i = 0; i < tasks.length; i++) {
if (tasks[i].id === id) {
tasks.splice(i, 1);
break;
}
}
}
function listTasks(filter) {
for (var i = 0; i < tasks.length; i++) {
if (filter === "all" || (filter === "completed" && tasks[i].completed) || (filter === "pending" && !tasks[i].completed)) {
console.log(tasks[i]);
}
}
}