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

Anik Devaughn
Anik Devaughn
7,751 Points

Challenge Task 1: Using the filter and reduce methods on the purchaseItems array, add the total price of all the......

Please help !! My code: 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.price === 'groceries') .reduce((sum, items) => sum + items.price, 0) .toFixed(2);

console.log( groceryTotal);

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.price === 'groceries')
.reduce((sum, items) => sum + items.price, 0) 
.toFixed(2);

console.log( groceryTotal);

2 Answers

Steven Parker
Steven Parker
220,682 Points

I see a few issues:

  • the filter should examine the dept of the items instead of the price.
  • the total should be left as a number and not converted into a string (as toFixed does)
  • you don't need to log anything to the console
Anik Devaughn
Anik Devaughn
7,751 Points

Thanks, it working :)