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Start your free trial###### Gary Calhoun

10,317 Points# Not really sure if I am doing this correctly...

```
var userNumber = parseInt(prompt("Enter a number"));
var userNumber2 = parseInt(prompt("Enter another number"));
var randomNumber = Math.floor(Math.random() * userNumber * userNumber2 ) + 1;
document.write(randomNumber);
```

## 5 Answers

###### Daniel Santos

34,969 PointsHi Gary,

I think the problem is that you should subtract "userNumber - userNumber2"

```
var entry1 = prompt("Please type a number");
var integer1 = parseInt(entry1);
var entry2 = prompt("Please type another number");
var integer2 = parseInt(entry2);
var randomNum = Math.floor(Math.random() * (integer2 - integer1 + 1)) + integer1;
document.write(randomNum)
```

If still stuck, post back

-Dan

###### Gary Calhoun

10,317 PointsThanks for the reply Dan. Ok so a user enters two different numbers twice, then the console generate a random number and then we subtract userNumber from userNumber2 add 1 to it and round off the decimal with the Math.random function. I am not sure why I am subtracting it though.

###### Daniel Santos

34,969 PointsThe reason you are subtracting is for the algorithm to work. I actually forgot that you have to add it back after you multiply to Math.random() number. I will do the steps for you:

```
var entry1 = prompt("Please type a number");
var integer1 = parseInt(entry1);
var entry2 = prompt("Please type another number");
var integer2 = parseInt(entry2);
var randomNum = Math.floor(Math.random() * (integer2 - integer1 + 1)) + integer1;
document.write(randomNum)
// Lets say integer1 = 8 and integer2 = 10
// First you do integer2 - integer1 = 2
// Then you add 1, so right it will be 3
// After that, Math.random() will generate a random number, lets say it is 0.82.
// 0.82 * 3 = 2.46
// Then Math.floor() will round it down to 2
// Lastly you add integer2 + 2 = 10
// So the output is 10. This correct because 10 is between 8 and 10.
```

I hope this help, I just broke it down for you step by step. If still don't understand let me know.

###### Gary Calhoun

10,317 PointsOh ok I understand now. Thanks for the breakdown I was so caught up about adding or multiplying variables that I didn't actually take the time to do the math.

###### Christopher Johnson

12,829 PointsThis actually doesn't make sense to me, your breakdown at least. Everything is smooth until the second to last line where you state, "Lastly you add integer2 - 2 = 10 (Which isn't even addition, but actually subtraction, and integer2 - 2 would = 8 not 10). I don't think your reasoning is correct, but then again I could be wrong.

###### Daniel Santos

34,969 PointsThanks for pointing this out. I am sorry for the mistake, I already edited. On the other hand, I am just trying to help. And with some experience that I have, teaching, I discovered that the same method doesn't work for everyone. If you want I can try to explain it to you differently. Let me know if you still don't understand, and what you don't understand after the change.

###### Christopher Johnson

12,829 PointsI figured it was just a small mistake, but I was assuming I had missed something. I got it though, thanks.