Question on the Random Challenge code

Question

var newNumber = Math.floor(Math.random() * (randomNumberTwo - randomNumberOne + 1)) + randomNumberOne;
My questions is why do you need  the parenthesis around 
this
(randomNumberTwo - randomNumberOne + 1))
for it to work properly.  I know you need it for it to work, just looking for explanation on the purpose it serves.
Thanks

Mike Hatch · Answer

The official way of describing it is called Operator precedence (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Operator_Precedence). Scroll down to the Table area. It will show you the order of precedence for multiplication, addition, subtraction, etc. 
A simple example: 
```Javascript
let a = (1 + 2) * 3)      
a                            // 9 
// This is parsed from left to right because the parentheses take higher precedence.
```
If you instead typed:
```Javascript
let a = 1 + 2 * 3 
a                            // 7 
// This is parsed from right to left because multiplication takes higher precedence.
```

Jackson Monk · Answer

You are just using basic math order of operations, telling the interpreter that within the set of innermost parentheses is what you what to do first

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Andrew Denson

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Question on the Random Challenge code

2 Answers

Jackson Monk

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Mike Hatch

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