I am coding a JS class which holds a price number and a ratings array of numbers. I have already written a getAverageRating method that returns the average of the numbers in ratings, and am now trying to code a valueMeter method that takes the average of every value in ratings, divides it by the price, and multiplies it by a hundred (no comment on the relevancy of such a method). Rather than re-writing the code to calculate the average, I am trying to use my getAverageRating method.

class Media {
  constructor(price) {
    this.ratings = [3, 4, 5];
    this.price = price;
  }

  getAverageRating() {
    let sum = 0;
    let amt = 0;
    this.ratings.forEach((rating) => {
      sum += rating;
      amt++
    })
    return sum / amt;
  }

  valueMeter() {
    let value = (this.getAverageRating()/this.price) * 100;
    return value;
  }
}

You can see I tried calling this.getAverageRating() inside of valueMeter, but calling the valueMeter method logged ‘NaN’.

const obj = new Media(30);

console.log(obj.valueMeter());
# logs 'NaN'

I expected the issue to come from the division, but even if I try to return only the this.getAverageRating call, it is still outputting ‘NaN’.

...
valueMeter() {
    let value = this.getAverageRating;
    return value;
...
console.log(obj.valueMeter());
# still logs 'NaN'