Bonfire 31: Sum All Primes

TASK: Sum all the prime numbers up to and including the provided number.

function sumPrimes(num) {

var total = 0;
// check if n is prime by dividing n for all numbers up to n-1
function isPrime(x) {
if (x<2) {return false;}

for (y=2; y<x; y++) {
if (x%y===0) {return false;}
}
return true;
}
//loop through numbers up to num
// if they pass the test, add them to the total
for (i=num;i>1;i--){

if (isPrime(i)){
total+=i;}

}

return total;
}


sumPrimes(10);