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JavaScript

Posted by charles bempah
charles bempah
1,295 Points

Formula looks right but random number generated isn't right. Someone please explain.

https://w.trhou.se/6fg6kggfx3

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,974 Points
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,974 Points

The proper random formula is:

Math.floor(Math.random() * (max - min + 1) ) + min;

Using your variables:

Math.floor(Math.random() * (userNumber2 - userNumber + 1) ) + userNumber

they are reversed.

parseInt on it's own won't update userNumber. The result needs to be assigned:

var userNumber = prompt(`Please type in a random number`);
userNumber = parseInt(userNumber);
var userNumber2 = prompt(`Please type in a second random number`);
userNumber2 = parseInt(userNumber2);

Otherwise:

Math.floor(Math.random() * (userNumber2 - userNumber + 1) )

generates a number. But the following is concatenated 

+ userNumber