Use
Array.prototype.reduce()
, the reduce() method applies a function against an accumulator and each value of the array (from left-to-right) to reduce it to a single value.
var array = [{
"adults": 2,
"children": 3
}, {
"adults": 2,
"children": 1
}];
var val = array.reduce(function(previousValue, currentValue) {
return {
adults: previousValue.adults + currentValue.adults,
children: previousValue.children + currentValue.children
}
});
console.log(val);