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JavaScript JavaScript Basics (Retired) Working With Numbers Create a random number

Posted by Sam johnson
Sam johnson
Courses Plus Student 688 Points

Is this Ok?

alert("Roll a dice?"); var random = parseInt(Math.random() * 7); alert(random);

It worked but is it a good practice?

Thank you

3 Answers

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points

Math.random()*6 returns a random number between 0 (inclusive), and 6 (exclusive). So 0 to 5.99999999....

Math.floor() makes this 0 to 5.

Adding 1 makes it 1 to 6.

Sam johnson
Sam johnson
Courses Plus Student 688 Points

oh ok Thanks

Ar33ss Leon
Ar33ss Leon
4,621 Points
Ar33ss Leon
Ar33ss Leon
4,621 Points

I used this

var providedNumber = prompt("Provide a number limit");
document.write(Math.ceil(Math.random() * providedNumber));
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points

If you want to roll a die your valid values are 1 to 6. What you have above also includes 0 as a possible outcome. You will want to use the standard formula instead:

Math.floor(Math.random() * 6) + 1;
Sam johnson
Sam johnson
Courses Plus Student 688 Points

But 6+1 is the same as 7 right? Or am i missing something?