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JavaScript JavaScript Basics (Retired) Working With Numbers The Random Challenge Solution

Paula Mourad
Paula Mourad
5,154 Points
Posted by Paula Mourad
Paula Mourad
5,154 Points

Top number?

I don't understand why he added the "topNumber".

2 Answers

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

:point_right: The topNumber is the largest possible random pick.

By itself, the random function returns a number from 0 up to (but not including) 1. So by multiplying it by the largest number you want possibly picked, you expand the range.

Steven Pozega
Steven Pozega
14,926 Points
Steven Pozega
Steven Pozega
14,926 Points

Using the prompt() method will always return a string, even if the user types in a number. So when the topNumber variable is declared it changes it to an interger with the parseInt method so that it can be used in the Math.random function.