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JavaScript JavaScript Array Iteration Methods Combining Array Methods Combining filter() and reduce()

Posted by Kennedy Malonga
Kennedy Malonga
18,790 Points

help please

Unexpected token +

app.js 
const purchaseItems = [
    {
        name: 'apples',
        dept: 'groceries',
        price: 2.49
    },
    {
        name: 'bread',
        dept: 'groceries',
        price: 2.99
    },
    {
        name: 'batteries',
        dept: 'electronics',
        price: 5.80
    },
    {
        name: 'eggs',
        dept: 'groceries',
        price: 3.99
    },
    {
        name: 't-shirts',
        dept: 'apparel',
        price: 9.99
    }
];
let groceryTotal;

// groceryTotal should be: 9.47
// Write your code below
groceryTotal = purchaseItems.filter(items => items.dept === 'groceries')
.reduce((sum + items.price) => sum + items, 0);

2 Answers

joejee
joejee
10,141 Points
joejee
joejee
10,141 Points

Reduce method cannot be used with an object. Try this

groceryTotal.map(item => item.price).reduce((sum, price) => sum+price);

Juan Luna Ramirez
Juan Luna Ramirez
9,038 Points
Juan Luna Ramirez
Juan Luna Ramirez
9,038 Points

There is a syntax error in your reduce function. It should be (sum, item) => sum + item.price

// I'm omitting the items in the array to keep it short
// const purchaseItems = [...]

let groceryTotal;

groceryTotal = purchaseItems
  .filter(item => item.dept === 'groceries')
  .reduce((sum, item) => sum + item.price, 0)