var myArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
var sum = myArray.reduce(function(previous, current) {
return previous + current;
}, 0);
var newArray = myArray.map(function(currentElement) {
return sum - currentElement;
});
console.log(newArray);
Output
[ 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45 ]