Get the avarage value of array with objects one key value - Javascript

Question

I have an array of users with ages, I want to get the average age of users. So far I tried to do it with reduce but it won't implement it's not the right syntax for reduce.

Here is my code:

let sam = { name: "Sam", age: 21 };
let hannah = { name: "Hannah", age: 33 };
let alex = { name: "Alex", age: 24 };

let users = [ sam, hannah, alex ];

function getAverageAge(array){
  let sumAge = array.age.reduce(function(sum, current) {
    return sum + current;
  }, 0)

  return (sumAge / (array.length + 1));
}

console.log( getAverageAge(users) ); // 21 + 33 + 24 / 3 = 26

In this case, it should return 26.

The objects you're iterating over are objects, not numbers, so `current` will be an object - you have to access the object's `age` property to get to the number (and change `(array.length + 1)` to `(array.length)` — CertainPerformance, Aug 26 '19 at 10:00
@CertainPerformance I don't want to get sum I want to get an average. — Robert Hovhannisyan, Aug 26 '19 at 10:06
You need to get the sum in order to get the average (at least, following your approach) — CertainPerformance, Aug 26 '19 at 10:07
@robertHovhannisyan if you have the sum, you can get the average too, it's simple maths after that. — Vaibhav Vishal, Aug 26 '19 at 10:08
Also don't feels offended if your question gets marked as duplicate, people are just trying to help you by pointing to other questions that already have a good answer for similar question — Vaibhav Vishal, Aug 26 '19 at 10:10
@VaibhavVishal so with that logic it means that your answer is pointless? — Robert Hovhannisyan, Aug 26 '19 at 10:13
@VaibhavVishal sorry that I don't live up to your expectations — Robert Hovhannisyan, Aug 26 '19 at 10:30

score 2 · Accepted Answer · answered Aug 26 '19 at 10:02

Arrays don't have a age property it is your object that has it:

let sam = { name: "Sam", age: 21 };
let hannah = { name: "Hannah", age: 33 };
let alex = { name: "Alex", age: 24 };

let users = [ sam, hannah, alex ];

function getAverageAge(array){
  const sumAge = array.reduce(function(sum, current) {
    return sum + current.age;
  }, 0)

  return (sumAge / array.length);
}

console.log( getAverageAge(users) );

Get the avarage value of array with objects one key value - Javascript

1 Answers1