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Tommy Bo
632 PointsWhat is the meaning and how does the equation (highnumber - lownumber + 1) make sense?
I don't understand the equation:
Math.floor( Math.random () * (highInput - lowInput ) + lowInput );
Why and how does this make sense mathematically? So far I reason that because we want to find a number between 3-7, let's say, we first have to find out the number of numbers in between the lowest and highest, otherwise known as the difference.
Then, after finding that out, we multiply 4 with the randomly generated number, which is a number including 0 up to but not including 1. So 4 * 0.99 = 4.99.
We round that number down to 4 and add the lowest input of 3 which produces 7. So we have a number between 3 and 7.
Is there another way to solve this and did I get the meaning right?
Thank you and much appreciated.
1 Answer
Blaize Pennington
13,879 PointsSo you are missing a 1.
Math.floor (Math.random() * (highInput - lowInput + 1) + lowInput )
Math.floor ( Math.random() * (7 - 3 + 1) + 3);
// Parentheses first
Math.floor ( Math.random() * (5) + 3);
// Then multiply
// lowest possible answer 0 * 5
Math.floor ( 0 + 3) //results in 3 and gets rounded down to 3.
// highest possible answer .99999999999999 * 5
Math.floor ( 4.99999999 + 3 ) // results in 7.999999999 which gets rounded down to 7.
Tommy Bo
632 PointsTommy Bo
632 PointsThank you!