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

Posted by Chris Ijoyah
Chris Ijoyah
3,271 Points

I don't understand how Math.ceil could return zero, if Math.random produces a number between 0 and 1.

Surely if Math.random produces a number between 0 and 1 and Math.ceil is called, any number created would be rounded up to 1.

2 Answers

Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Chris,

Math.random() can return any number from 0 up to but not including one. It can return zero but not 1.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/random

Nicholas Kim
Nicholas Kim
2,884 Points
Nicholas Kim
Nicholas Kim
2,884 Points

I tried this code to see if this was possible. Try running it in your local environment

for(var index = 0 ; index < 1e10 ; index++){ if(Math.ceil(Math.random()) == 0 ){ alert("Found!"); } }

The code basically runs for 1e10 times to see if Math.random() can produce a 0.0000000...