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

how do I complete this callback function?

I cant tell if I'm using the right properties to accurately use these callback methods. I think I'm somewhat close but any hints would be appreciated, thanks.

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(grocItem => grocItem.dept === 'groceries')
  .reduce((sum, grocItem) => sum + grocItem // this is where im stuck...) ;

console.log(groceryTotal);

1 Answer

Steven Parker
Steven Parker
217,627 Points

Yes, you were pretty close! But remember that after the filter, you still have an array of item objects, but you want to sum only their prices. Plus, you'll need to provide 0 for the initial value of sum:

//                                         👇 only sum prices
  .reduce((sum, grocItem) => sum + grocItem.price, 0);
//                                                 👆 starting with 0

ok thanks Steven for clarifying. that's what it was, I had trouble figuring out how to solely add the prices , I always overthink these challenges ha. thank you for your help!