Ok, so chrome console works same on all the pages.

I opened the console by pressing (F12) key on keyboard.

Then i wrote this code :

```
function isPrime(num){
var remainder = [];
var squareroot = Math.floor(Math.sqrt(num))
for(let i=2;i<squareroot;i++){
remainder.push(num%i);
}
if(remainder.includes(0)){
return false;
}
return true;
}
```

The logic that goes behind this code is :

**1)** When i wish to find out whether a number is prime or not, what i have to do is check its divisibility by all the numbers which are less than squareroot of that number.

**2)** If a number has squareroot in decimal values(which most of the numbers have), then i just convert that into integer by `Math.floor()`

function.

**3)** If the number is not divisble by any of the numbers less than its squareroot, it is a prime number.

**4)** So, in the code, i declared an empty array `"remainder"`

first and then, i calculated the squareroot of the num and converted it into integer. And then, i started the loop with initial value of 2 because if it initializes with 1, num will always be divisible by 1.

**5)** Now, num is divided and by all the number in loop, and the remainder is pushed to remainder array.

**6)** If the num is divisible by any of the values in loop, the remainder array will have 0 as one of its elements.

**7)** Thus, if remainder array contains 0 function `isPrime()`

returns false else it returns true i.e the number is prime.

**I have checked for several test cases and function works all the time.**

But when it is inside the `sumPrimes()`

it does not work.