Reduce method in Javascript - Mini Project: Build & Apply

Sum of Prices Using the Reduce Method

📖 Scenario: You are managing a small online store. You have a list of products with their prices. You want to find out the total price of all products combined.

🎯 Goal: Build a program that uses the reduce method to calculate the total price of all products in the list.

📋 What You'll Learn

Create an array of product objects with exact names and prices

Create a variable to hold the initial total price

Use the reduce method with a callback function to sum all product prices

Print the final total price

💡 Why This Matters

🌍 Real World

Calculating totals is common in shopping carts, budgets, and reports.

💼 Career

Knowing how to use reduce helps in data processing and summarizing information efficiently.

1

Create the products array

Create an array called products with these exact objects: { name: 'Book', price: 15 }, { name: 'Pen', price: 5 }, { name: 'Notebook', price: 10 }.

Javascript

// Your code here

Need a hint?

Use square brackets [] to create an array and curly braces {} for each product object.

2

Create the initial total variable

Create a variable called initialTotal and set it to 0.

Javascript

const products = [
  { name: 'Book', price: 15 },
  { name: 'Pen', price: 5 },
  { name: 'Notebook', price: 10 }
];
// Your code here

Need a hint?

Use const to create a variable that holds the starting total price.

3

Use reduce to calculate total price

Create a variable called totalPrice and set it to the result of calling products.reduce with a callback function that adds the current product's price to the accumulator. Use initialTotal as the starting value.

Javascript

const products = [
  { name: 'Book', price: 15 },
  { name: 'Pen', price: 5 },
  { name: 'Notebook', price: 10 }
];
const initialTotal = 0;
// Your code here

Need a hint?

The reduce method takes a function with two parameters: the accumulator and the current item. Add the current product's price to the accumulator.

4

Print the total price

Write a console.log statement to print the value of totalPrice.

Javascript

const products = [
  { name: 'Book', price: 15 },
  { name: 'Pen', price: 5 },
  { name: 'Notebook', price: 10 }
];
const initialTotal = 0;
const totalPrice = products.reduce((accumulator, product) => accumulator + product.price, initialTotal);
// Your code here

Need a hint?

Use console.log(totalPrice) to show the total price in the console.