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JavaScript JavaScript Numbers The Math Object Random Number Challenge – Solution

Tall Toad
Tall Toad
2,746 Points

Why is console.log() not having an issue showing numbers without the parseInt?

// Collect input from a user

const choosenNumber = prompt("Whats your favourite number?");

// Convert the input to a number const favouriteNumber = (choosenNumber);// I know parseInt should be present before the (chosenNumber). But when I run this workspace on the browser, I'm not getting any errors or Nan.

// Use Math.random() and the user's number to generate a random number

const randomNumber = Math.floor( Math.random() * choosenNumber) + 1;

// Create a message displaying the random number

console.log(${randomNumber} is a number between 1 and ${favouriteNumber}.);

1 Answer

Steven Parker
Steven Parker
231,184 Points

For some operations, JavaScript can tell that a number is needed and it performs type coercion, which is essentially converting the string into a number for you automatically.

But you don't want to rely on this, since there will be other cases where it can't perform this for you. Here's an example where it won't work:

const choosenNumber = prompt("Whats your favourite number?");
const twice = choosenNumber + choosenNumber;
console.log(`${choosenNumber} added to itself is not ${twice}, is it?`);
Tall Toad
Tall Toad
2,746 Points

Thanks for the reply Steven Parker, I'm new to coding. Some parts make sense some don't or eventually do. As a newbie, How does one evaluate if they are doing well or not?

Steven Parker
Steven Parker
231,184 Points

If you generally complete the quizzes and challenges with only occasionally needing to review a lesson, you're doing quite well indeed!