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JavaScript

Maggie Lodge
Maggie Lodge
3,373 Points

Random number function question

What is the difference between these two lines of code? They both return random numbers in the Console log.

  const randomNumber = Math.floor(Math.random() * (upper-lower+1)) + lower;
  const randomNumber = Math.floor(Math.random() * (upper)) + lower;

1 Answer

Steven Parker
Steven Parker
229,967 Points

The first line implements the standard formula for a random number between (inclusively) two values. For example, if "lower" was set at 100 and "upper" was set at 200, the final result would always be at least 100 and never higher than 200.

The second line isn't a standard formula. Given the same example with "lower" and "upper" set at 100 and 200, the value generated would also be at least 100 but could be as high as 299.