Array reducer

// If you're using an array of objects you should use this one.
let arrayOfObjects = [
    { name: "paper", quantity: 100, unitPrice: 1.96 },
    { name: "pen", quantity: 57, unitPrice: 1.22 },
    { name: "eraser", quantity: 6, unitPrice: .35 }
]

let totalObjectsPrice = arrayOfObjects.reduce((acc, { quantity, unitPrice }) => {
  return acc + Math.round(quantity * unitPrice);
}, 0);

// If you're using an array of integers you should use this one.
let arrayOfNumbers = [196, 69.53, 2.09];

let totalNumbersPrice = arrayOfNumbers.reduce((prev, next) => Math.round(prev + next));

console.log(["array of objects price: ", totalObjectsPrice, " array of numbers price: ", totalNumbersPrice])