IQ even odd test

iqevenoddtest.js

function iqTest(numbers){
numbers = numbers.split(" ");
  var even = numbers.filter(function(number) {
    return number % 2 === 0; 
  });
  var odd = numbers.filter(function(number) {
    return number % 2 !== 0; 
  });
  console.log(even, odd);
  if(even.length > odd.length) return numbers.indexOf(odd[0])+1;
  return numbers.indexOf(even[0])+1;
}