1-percentage-change.js

let carPrice = "10,000";
let priceAfterOneYear = "8,543";

carPrice = Number(carPrice.replaceAll(",", ""));
priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));

const priceDifference = carPrice - priceAfterOneYear;
const percentageChange = (priceDifference / carPrice) * 100;

console.log(`The percentage change is ${percentageChange}`);

// Read the code and then answer the questions below

// a) How many function calls are there in this file? Write down all the lines where a function call is made
// There are 4 function calls in this file. The lines where a function call is made are:
// Line 1: carPrice.replaceAll(",", "")
// Line 2: priceAfterOneYear.replaceAll(",", "")
// Line 3: Number(carPrice.replaceAll(",", ""))
// Line 4: Number(priceAfterOneYear.replaceAll(",", ""))
// line 10: console.log(`The percentage change is ${percentageChange}`);

// b) Run the code and identify the line where the error is coming from - why is this error occurring? How can you fix this problem?
// Error on line 5 where comma was missing in replaceAll function call. 

// c) Identify all the lines that are variable reassignment statements
// Line 4: carPrice = Number(carPrice.replaceAll(",", ""));
// Line 5: priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));

// d) Identify all the lines that are variable declarations
// Line 1: let carPrice = "10,000";
// Line 2: let priceAfterOneYear = "8,543";
// Line 7: const priceDifference = carPrice - priceAfterOneYear;
// Line 8: const percentageChange = (priceDifference / carPrice) * 100;

// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
// The expression Number(carPrice.replaceAll(",","")) is first calling the replaceAll method on the carPrice string to remove all commas from the string. This is necessary because the presence of commas in a number string can cause issues when trying to convert it to a number. After the commas are removed, the resulting string is passed to the Number function, which converts the string into a numeric value. The purpose of this expression is to convert the carPrice string, which may contain commas, into a number that can be used for calculations.